Data

Data Analysis¶

Data Analysis provides a possibility to carry out many different analyses based on a set of different time series tools as well as a few spatial tools. Apart from the data coverage and zonal statistics tools all these tools are customized tools created by the user. This ensures that the user only has the tools available that are actually needed and used, and it also provides an opportunity to customize and later modify the tools to the need of the user. For most tools the output are a chart and/or a table but it can also be data coverage or a map.

A description is given on how to create and use the data analysis tools, as well as a brief description of the basic time series based on which the customized tools are created.

Create Data Analysis Tools¶

A Tool carry out simple data analysis of selected time series (or spatial data), which can be presented as a Table or a Chart accessed by clicking on the Table, Chart or Apps button under the Analysis menu.

The User create the customized tools based on a set of more than 20 basic analysis tools available in the system. Once the tools have been created, they will be available from the Analysis menu. Tools can be modified or removed depending on the need of the user.

Note: The created tools will be saved in the actual database that the user are working on. Thus, when the user make a backup of the database and the database later is restored by the user or another user, the created tools will be available along with the data in the database.

Add Tools for Analysis¶

When selecting the Tools button in the Tools Settings the Tools configuration dialog box appears, which allows you to add and configure Tools and Apps to be accessible from the Analysis menu. Tools can be added, edited or removed, and given a display name, which will appear in the drop down lists under the Analysis menu.

Dialog for adding and configuring tools and apps to be accessible in the Analysis menu.

Add a Tool with a Chart Output¶

The first step to create and include Tools with Chart output is described below, and a tool to calculate the Duration Curve of a streamflow time series is used for illustration purpose). The first step is:

Under the Settings click on Tool settings
Click on tools button in the Tools Settings to open the Tools configuration dialog:
Click on Add to open the Add new tool dialog, where the Tool is configured;
Specify the Display name (to appear in the Analysis menu) of the Tool
Select the tool from the list of tools under Tool name;
Select the Chart from the Output list, Click on Add tool and the Tool will appear in the list in the Tools configuration dialog.
Some tools may require additional specifications in the properties box to the right. In the Description of Basic Data Analysis Tools more details are provided for the individual tools.
Click Close.

Add a Tool with Table Output¶

Follow the same steps as for Tools with Chart Output except chose Table from the Output list.

Add an Apps¶

Follow the same steps as for Tools with Chart or Table Output. For Apps only three tools are available:

No Output can be chosen because an Apps has its own interface.

The tools for Apps will require additional specifications depending of the tool selected (see Description of Basic Data Analysis Tools).

Use Data Analysis Tools¶

If a data record is selected in the station list below the Map view it can be analysed using predefined Tools and Apps configured in the Tools settings. The Tools and Apps are accessible from the Analysis menu ribbon.

Analysis menu ribbon buttons

Available button options under the Analysis menu are:

Period drop down list with pre-defined periods for analyses;

Coverage button to view the data coverage of the stations selected in the

data records list;

the Charts drop down list of tools providing output in the form of Charts;

the Tables drop down list of tools providing output in the form of Tables;

the Apps drop down list of tools providing output in the form of Apps;

the zonal statistics tool that allows aggregation raster cell values over a polygon, e.g. calculating the average precipitation over sub-basins.

Analyse Data with a Tool (Chart Output)¶

To analyse data series with a Tool that displays the result as a Chart, click on Chart drop down button in the Analysis menu and select one of the available Tools.

The available configure analysis tools specified in the Tool Settings will appear in the Tools drop down list for time series analysis.

Analyse Data with a Tool (Table Output)¶

To analyse data series with a Tool that display the result as a Table, click on Table drop down button in the Analysis menu and select one of the available Tools.

Selection of Tools producing Tables from the Table drop down list for time series analysis.

Resulting Table from the Analysis (Example: Monthly flow and statistics)

Data Analysis with Apps¶

To analyse data series with Apps click on Apps drop down button in the Analysis menu and select one of the available Apps. Apps provide an Interface allowing you to configure the plot.

The format of the index curves is configured when creating the Apps.

Two examples of the Time Series Index Apps, which either display the curves as a single x-axis plot or a multiple x-axis plot. For the former, up to three years can be shown together with index curves. For the latter, a continuous time series for a specified period can be shown together with index curves.

Configure Periods for Data Analysis¶

When selecting the Periods button

in the Tool settings a dialog appears to specify pre-defined time periods for which time series analysis are carried out and displayed. This functionality is useful for doing analysis for specific periods of time. It provides an automated procedure for consistent analysis of many data records, covering the same period.

Dialogs for specifying pre-defined periods (years) and sub-periods (dates) for which the time series are carried out.

Select a Period for Analysis¶

The Period button in the Analysis menu ribbon is used to select one of the periods defined under the Tools Settings Defining Periods.

Example showing the Period pull down menu for selecting the time period, e.g. for duration curve analysis of the dry season flow during the period defined by the Decade80 (1981-1989).

Analyse Spatial Data with Zonal statistics¶

Spatial data can be analysed with zonal statistics tool. The tool summarizes the values of a raster within the zones of a polygon vector layer and reports the results in a map and as a new temporary layer.

When a user click on Zonal statistics a new map window will open where the user can specify the zone layer, the input raster layer and the output statistics.

Description of Basic Data Analysis Tools¶

Accumulation¶

Tool Name	Accumulation
Description	This tool calculates the accumulation of all values in a time series. However, note that this is not the same as summing the values. For rates and instantaneous values, accumulation is calculated by multiplying the values by the time period they are applicable.
Input items	One or more time series
Tool properties	No properties to be defined
Output details	A table with the accumulated values for the selected time series or a chart (histogram) with the accumulated value for each of the selected time series.
Output example	Chart: Accumulated values for five selected time series (histogram): Table: Accumulated values for five selected time series
Technical reference and usage tips

Annual Maximum¶

Tool Name	Annual Maximum
Description	Calculates the annual maximum value for each water year. This tool is important in relation to flooding and design of various infrastructure, such as bridges, culverts, etc.
Input items	One or more time series
Tool properties	The start date of the water year has to be indicated – default is 1 Jan. Day: Indicate the start day of the water year. Month: Indicate the start month of the water year.
Output details	A chart or table with the annual maximum values for each water year
Output example
Technical reference and usage tips	When choosing to show as chart, you can then also see the values as a table by selecting “Show values” in the toolbar.

Annual Maximum series (seasonal)¶

Tool Name	Annual Maximum Series (Seasonal)
Description	Calculates the annual maximum value for each water year within the specified season. It is very simular to the Annual Maximum tool, except that this tool calculates the maximum within a given season defined by the user. This tool is important in relation to flooding and design of various infrastructure, such as bridges, culverts, etc.
Input items	One or more time series
Tool properties	The user will need to define the following: Season start: Day and month. Season End: Day and month. Start of the Water Year: Day and month.
Output details	A chart or table with the annual maximum values for each water year
Output example	Chart output: The selected season is 1/7 to 31/1 and the water year starting 1 January:
Technical reference and usage tips	When choosing to show as chart, you can then also see the values as a table by selecting “Show values” in the toolbar.

Annual N-Day Minimum¶

Tool Name	Annual N-Day Minimum
Description	This tool identifies which time of the year does the mean minimum flow appear for a given duration (e.g. 10-days) specified by the user. Thus, if the user have specified a 10-days period, the tool will identify which 10 days for each water year is the mean flow for these 10 days at its minimum and it will return a chart or table with the last date of this period and the mean flow during this period.
Input items	One of more time series selected in the time series list
Tool properties	Number of days (n): Specifies the length (days) of the annual minimum.
Output details	It provides a time series indicating the date, i.e. last day of the N-days where the annual minimum has taken place, and the mean of the values during this N-day period.
Output example
Technical reference and usage tips

Average¶

Tool Name	Average
Description	The Average tool is used to calculate the simple mean and/or time weighted average of one or more time series. This tool is useful for many common water resources analysis.
Input items	One of more time series selected in the time series list
Tool properties	Time weighted average: True / False (defines wether the calculations shall weight the time series values with their duration).
Output details	A table, containing the average values and unit of the calculated time series.
Output example
Technical reference and usage tips	Remember to indicate in the Properties whether the averages should weight the time series values with their duration.

Coverage¶

Tool Name	Coverage
Description	The coverage tool shows the availability of data in the selected time series, allowing the identification of data gaps.
Input items	One of more time series selected in the time series list
Tool properties	None – this tool is already predefined as part of the installation and has its own “Coverage” tool in the toolbar.
Output details	A chart showing the available and/or missing data depending on what the user choose to see. Note: This tool provide the user with an interface where user can choose to show: 1) Periods with available data (Values), 2) Periods with missing data (Missing values), or 3) Both periods with missing and available data (All).
Output example	Data coverage for three selected discharge time series:
Technical reference and usage tips	By clicking in the upper left corner it is possible to either copy or print the chart

Cross-Correlation¶

Tool Name	Cross-Correlation
Description	This tool calculates the cross-correlation value of two hydrologic daily time series, using the cross-covariance between the two time series. Can e.g. be used to determine the probability that two rivers will peak at the same time, which is useful for main/tributary confluences and basin drainage analysis.
Input items	Two time series selected in the time series list. Note: The two selected time series must not have missing data.
Tool properties	None
Output details	Calculated cross correlation between the two selected time series
Output example
Technical reference and usage tips	Remember that the two selected time series must not have missing data and series should have the same start time.

Data Quantile¶

Tool Name	Data Quantile
Description	The Data quantile tool calculates the data quantile. The data quantile is the value that a specified fraction of all raw data are less than. For a fraction of 0.5 the data quantile equals the median.
Input items	One of more time series selected in the time series list
Tool properties	Fraction: Set a value between 0 and 1
Output details
Output example	Table output: Example of calculation of three different quantiles of one discharge time series: Q20 (fraction = 0.8), Q50-Median (fraction = 0.5) and Q80 (fraction = 0.2): Chart output: Example of Q50 of discharge from three different river gauging stations.
Technical reference and usage tips	Note: The fraction indicate the fraction of the records that are below that calculated value, while e.g. Q20 indicate the percentage of the records that are above Q20. This is the reason that a value fraction of 0.8 should be selected to calculate Q20.

Distribution¶

Tool Name	Distribution
Description	A distribution curve relates the magnitude of an observed variable to its frequency of occurrence. Integrating the distribution curve between two values yields the probability, P, of a given value, X, being inside that interval. This tool plots the probability distribution of the values in a time series. The time axis of the input time series is not taken into consideration.
Input items	One or more time series selected in the time series list
Tool properties	Distribution Type: 1) Cumulative Distribution Function (CDF) or Probability Distribution Function. Interval length: Specifies how long each value interval should be. Start Value: A start value can be defined,if for instance the lowest value is much higher than zero.
Output details	One distribution, chart or table, will be produced for each of the selected time series.
Output example	Distribution chart using the Cumulative Distribution Function (CDF): Distribution chart using the Probability Distribution Function (PDF):
Technical reference and usage tips

Drought Duration and Volume¶

Tool Name	Drought Duration and Volume
Description	The tool calculate the duration and deficit volume of periods where the values are below a user-defined threshold value. This is particularly useful in monitoring and management of droughts.
Input items	One of more time series selected in the time series list
Tool properties	Threshold: Define the threshold value. Duration and deficit volume will then be calculated for periods with values below the threshold value.
Output details	Two tables or charts for each selected time series providing the following information for each period where values are below the threshold value: 1) The first day in the period and the duration of the period and 2) the first day in period and the deficit volume for the period.
Output example	Table showing the first day of each period where values are below the user-defined threshold and the deficit volume for each deficit period:
Technical reference and usage tips

Duration Curve¶

Tool Name	Duration Curve
Description	A duration curve is based on the calculated exceedance probability for the range of values found in the time series being analysed. A duration curve shows the range of data values found in the time series as a function of the exceedance probability. An exceedance probability of zero means that there are no values above this value in the time series, while a probability of 0.95 (e.g. Q95 for discharge time series), means that 95% of the values in the time series is above this value.
Input items	One of more time series selected in the time series list
Tool properties	The tool has no properties
Output details	One duration curve (chart) or list of exceedance values (table) will be produced for each selected time series.
Output example	Flow duration curve generated for a discharge time series:
Technical reference and usage tips	When choosing to show as chart, you can then also see the values as a table by selecting “Show values” in the toolbar.

Flag Outliers¶

Tool Name	Flag Outliers
Description	This tool adds a user specified flag to the values in a time series that falls within a specified range. Flags can be added to the original input time series, or a copy of the series.
Input items	One of more time series selected in the time series list
Tool properties	The following properties need to be set: Criteria Option: The criteria at which the tool need to operate, which can be 1) Outside range, 2) Inside range, 3) Max. rate of change, or 4) Min. rate of change. Depending on what is selected different options will appear. Add flag to copy: Indicating whether the flags are added to a copy of the data series. Flag outliers: The flag used to flag the values that fulfills the outlier criteria specified by the user. Replace existing flags: Skip already flagged time series (true) or not (false).
Output details	One time series will be produced
Output example
Technical reference and usage tips

Maximum Value¶

Tool Name	Maximum Value
Description	The Maximum value tool calculates the maximum value of one or more selected time series. The values can be shown in either a table or a chart. This is very useful for many applications. Furthermore, the tool may be used when custumizing other tools such as or.
Input items	One of more time series selected in the time series list
Tool properties	None
Output details	Table or chart
Output example	Chart: The tool has calculated the maximum values for six selected discharge time series:
Technical reference and usage tips

Minimum Value¶

Tool Name	Minimum Value
Description	The Minimum value tool calculates the minimum value of one or more selected time series. The values can be shown in either a table or a chart. This is very useful for many applications. Furthermore, the tool may be used when custumizing other tools such as or.
Input items	One of more time series selected in the time series list
Tool properties	None
Output details	Table or chart
Output example	Table: The tool has calculated the minimum values for six selected discharge time series:
Technical reference and usage tips

Monthly Statistics¶

Tool Name	Monthly Statistics
Description	This tool provide an opportunity to prepare a summary table showing the montly statistics for the selected time series. This is a very useful tool to get an overview of the statistics of a time series, and suitable for preparation of tables for reports.
Input items	One or more time series selected in the time series list
Tool properties	Monthly statistics: Tool to apply: Indicated the wanted statistics, e.g. average. Monthly summary: Indicate whether a monthly summary (based on all the years in the record) shall be prepared or not (True/False) for average, maximum and minimum, respectively. Period: Here the user select the first and the last month. This is a possibility to customize the water year (when it starts and ends) or to exclude some of the months if wanted. Yearly summary: Indicate whether a yearly summary shall be prepared or not (True/False) for average, maximum and minimum, respectively.
Output details	A table showing the monthly statistics for each month in the selected time series. If chosen in the proporties, it also can provide monthly and yearly summaries.
Output example
Technical reference and usage tips	Use the “Fit column width to view” and “Set the number format” tools to easily make your table looks nice. The table can be printed, and copied to Excel for further work. NOTE: If a number of long time series are selected then calculations may take some time to carry out due to the comprehensive underlying calculations to prepare the table.

Periodic Statistics¶

Tool Name	Periodic Statistics
Description	This tool prepare statistics for a given periodic frequency, which can be hourly, daily, weekly, monthly or yearly.
Input items	One or more time series selected in the time series list
Tool properties	Output value type: Mean Step Accummulated or Reverse Mean Step Accumulated are available. Period: Select between the following frequencies: Hourly, Daily, Weekly, Monthly or Yearly. Tool to apply: Select the tool to use, e.g. average, accumulation, etc.
Output details	A table or chart showing the calculated period statistics
Output example	Table showing the rainfall from a station converted to annual totals, using a yearly frequency and applying the “Accumulation” tool:
Technical reference and usage tips	Be careful when selecting the Output value Type.

Rate of Change¶

Tool Name	Rate of Change
Description	This calculates the rate of change of the selected time series, e.g. how much the flow in a river may change from one day to the other. The rate of change can e.g. be used for quality control of time series.
Input items	One of more time series selected in the time series list
Tool properties	Suffix: A user selected suffix added to the name of the original time series. Unit: The time unit for which the rate of change want to be calculated. The possible choices are: Second, Minute, Hour or Day.
Output details	A chart or table showing the calculated rate of change
Output example	Example of the rate of change for a discharge time series, where the rate of change per day has been calculated:
Technical reference and usage tips	When selecting chart as the output, it is still possible to see the result in a tabular form by clicking on “Show Values” in the toolbar.

Resample¶

Tool Name	Resample
Description	The resample tool is used to change the time step of a time series into a user specified time step. It is possible to resample into larger and smaller time steps.
Input items	The use of the resample tool requires that at least one time series has been selected. If more than one time series are selected, the same user specified options will be applied to all the selected time series.
Tool properties	Interpolate across gaps: False/True. This property determines if the algorithm shall interpolate across gaps in the input time series. If set to true, the algorithm will interpolate across gaps that are less than a specified duration/number. If set to false the gaps in the input time series will result in gaps in the output time series. New time step: The user will define the frequency of the resampling which can be selected from 1 second to several years. Start time: This option is used to force the resampling tool to start at a specific point of time. The user can select between none, day or Specific Date Time. When selecting None the first time step in the original time series is used. The two other options are described in the explanation in the tool itself.
Output details	One resampled time series for each input time series.
Output example	Example of a discharge time series which is resampled on a daily basis: Example of the same discharge time series resampled with monthly time steps:
Technical reference and usage tips	If a time series is resampled into a larger time steps, the resulting values will be calculated as: Instantaneous: The values of the larger steps are calculated by linear interpolation between the two nearest small time step values. Accumulated: The time average of the small-step accumulation rate is used to derive the accumulated values for the large time steps. Mean step accumulated time series: The large time step is the time averaged value of the sub-steps. Step accumulated: The temporal average of the small-step accumulation rate is used to derive the step accumulated values for the large time steps. Reverse mean step accumulated: The large time step is the time averaged value of the sub-steps. If the time series are resampled into smaller time steps, the resulting values are calculated as: Instantaneous: The values of the sub-steps are calculated by linear interpolation between the two nearest large time step values. Accumulated: The accumulation rates of the large time steps are used to derive the accumulated values for the small time steps. Mean step accumulated time series: The same values will be used for the sub-steps as for the large time step. If a sub-step is covered by two large time steps, the temporal average is used. Step accumulated: The temporal average of the large-step accumulation rate is used to derive the step accumulated values for the small time steps. Reverse mean step accumulated: The same values will be used for the sub-steps as for the large time step. If a sub-step is covered by two large time steps, the temporal average is used.

Standard Deviation¶

Tool Name	Standard Deviation
Description	The Standard deviation tool calculates the standard deviation of one or more time series. This provides, when compared with the mean flow, a good impression of the variation of the values in a time series.
Input items	One of more time series selected in the time series list
Tool properties	The tool has no properties.
Output details	A table containing two columns: Standard deviation Unit and one row for each input item.
Output example	Table with calculated standard deviation for three discharge time series:
Technical reference and usage tips

Statistics Map¶

Tool Name	Statistics Map
Description	The MapStatistics tool is only accessible from the Apps button under the Analysis menu tab. It is used to calculate simple statistics (average or accumulation) for the selected stations and show the result on a map. This tool is useful water resources analysis to evaluate the spatial variation of flow or rainfall for a given period.
Input items	A number of time series selected in the time series list.
Tool properties	Tool settings: Feature class group: Output folder for saved map (e.g. /MIKE INFO/Saved layers). Start of hydrological year: Month (number). Tool to Apply: Tool name (for (1) Flow data: Use Average tool and (2) Rainfall data: Use Accumulation tool).
Output details	A plot showing actual statistics at each station displayed as a gradient colour plot with Google satellite map as background. Note that Apps provide an interface for providing additional specification e.g. input data: Options: 1. Specify period (start year and end year) for the statistics 2. Click on for options to: 3. Save layer: (It will be available as a thematic layer) 4. Copy: (Copy to clipboard) 5. Export graphics: (Save as image file) 6. Background: Select different types of background 7. Isoline map: Include isolines
Output example
Technical reference and usage tips

Time Series Index¶

Tool Name	Time Series Index
Description	The TimeSeriesIndex tool is only accessible from the Apps button under the Analysis menu tab. It is used to compare monthly flow values with different threshold levels calculated using the within-year statistics tool of the monthly time series. This tool is useful in water resources assessment to evaluate e.g. low flow conditions and when the river flow reaches critical levels based on monthly statistics.
Input items	One of more time series selected in the time series list
Tool properties	Quantile settings: Number of quantiles: A number (defines the number threshold to be included). Colour of quantile: Colour specification. Filled: (1) True (filled colour below the threshold line) or (2) False (only line colour). Name of Quantile: Name specification of each quantile (e.g. 20%, 5% etc.) Quantile: A number, specifying the percentage of exceedence for the time series of monthly value(s) for a given month (e.g. all April values on record). Tool settings: Period: Monthly / daily. Start of hydrological year: Month.
Output details	A plot showing actual flow series together with threshold level curves. Note that Apps provide an interface for providing additional specification e.g. input data: Options: 1. Specify years to be plottet (max three years can be specified) using single year time axis 2. Click on and: 3. Click on Multiple year time axis and specify period (start year and end year); or 4. Syncronise y-axis (if more than one time series have been selected as input item); or 5. Print or Copy (to clipboard) the chart
Output example	Single time axis plot: Multiple years time axis plot:
Technical reference and usage tips

Time Series Threshold¶

Tool Name	Time Series Threshold
Description	The TimeSeriesThreshold tool is only accessible from the Apps button under the Analysis menu tab. The tool is used for comparing monthly flow values together with specified threshold levels. This tool is useful in water resources assessment to evaluate e.g. low flow conditions and when the river flow reaches critical levels.
Input items	One of more time series selected in the time series list.
Tool properties	Threshold settings: Number of thresholds: A number (defines the number threshold to be included). Threshold type: Constant (constant value over the year) or variation (monthly values). Threshold description (for each threshold): Colour of threshold: Colour specification; Filled: (1) True (filled colour below the threshold line) or (2) False (only line colour). Name of Threshold: Descrption associated for each threshold (e.g. normal, low, critical etc.). Threshold: Value(s) (a single flow value or twelve monthly values). Tool settings: Period: Monthly / daily. Start of hydrological year: Month (month number).
Output details	A plot showing actual flow series together with threshold level curves. Note that Apps provide an interface for providing additional specification e.g. input data: Options: 1. Specify years to be plottet (max three years can be specified) using single year time axis 2. Click on and: 3. Click on Multiple year time axis and specify period (start year and end year); or 4. Syncronise y-axis (if more than one time series have been selected as input item); or 5. Print or Copy (to clipboard) the chart
Output example	Single time axis plot: Multiple years time series plot:
Technical reference and usage tips

Within Year Statistics¶

Tool Name	Within Year Statistics
Description	The Within-Year Statistics tool calculates the specified statistics for a relative time period / analysis time step. The output is a time series that covers a single year (but are based on the the whole time series period) with the statistics calculated at the specified time steps. This is useful to get e.g. variation in e.g. mean daily or mean monthly flow over the year, or how many records are available per day throughout the year. Thus, it is a a very powerful tool to demonstrate the variation in flow regime over the year.
Input items	One or more time series selected in the time series list. The time series must cover at least one full year.
Tool properties	Within-year statistics: The statistics to be calculated, e.g. average, min., max., count, etc. Output time step unit: Daily or monthly. First day in output TS: Indicates what should be shown as the first day in the output time series. This is an artificial date, as the year shown represents the whole time series period, but this property allows the user e.g. to identify 1/10/1990 as the first date if the water year starts in October. Output time series suffix: A suffix which is added to the original time series name.
Output details	A chart or table showing the within-year statistics for each of the selected time series.
Output example	Example of annual statistics on a daily basis for a flow series, showing an excellent overview of the variation of flow regime throughout the year:
Technical reference and usage tips