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Dataset Class

The Dataset class represents one dataset loaded in PrestoPlot. It gives access to its properties/attributes and its data values.

The attributes can be :

  • dateformat : The original date format (see DateManager)
  • description : The dataset description.
  • name : The displayed name of the dataset.
  • source : Indicates the origin of the dataset (file name, computed, socket, ...).
  • unit : The dataset unit.
  • xlabel : The XLabel that can be displayed on graphs.

Public Functions

addPoint{ date value }
addPointRealTime{ date value }
addPoints{ dates values }
adjustDate{ from to format }
convertToSeconds{}
get{ attribute }
length
removeLabels{}
set{ attribute value }
setLabel{ value label }
sort{}
spreadlabels{ keepUnused }
x{ indexFrom indexTo }
y{ indexFrom indexTo }

Detailed Functions Descriptions

addPoint

addPoint{ date value }

Append a point at the end of the dataset. The point will not be inserted in the middle of the dataset if the date is within the current range (instead, the plot will go backward).

If you intend to add several points, prefer building a buffered list of x values and y values, and use addPoints

If you intend to add points in a real-time way (for example from a stream), prefer using addPointRealTime.

Parameters :

  • date : The point date in the unix GMT format.

  • value : The point value at the given date. The value can be either a double value or a label.

addPointRealTime

addPointRealTime{ date value }

Append a point at the end of the data vector. Use this function if you are feeding the dataset with a real-time stream. This function is optimized for real-time processing and it enables real-time features.

Do not use this function for a static initial data feeding.

Parameters :

  • date : The point date in the unix GMT format.

  • value : The point value at the given date. The value can be either a double value or a label.

addPoints

addPoints{ dates values }

Append a list of points at the end of the dataset. The points will not be inserted in the middle of the dataset if the dates are within the current range (instead, the plot will go backward).

If you intend to add points in a real-time way (for example from a stream), prefer using addPointRealTime.

Parameters :

  • dates : A list of dates in the unix GMT format.

  • values : A list of point values at the corresponding date in the dates list. The value can be either a double value or a label.

adjustDate

adjustDate{ from to format }

Adjust the dataset date. The given from date will become to date after the adjustment. All points will be time shifted of the amount (to - from).

Optionally, the date format can be changed.

The new dates are applied in place in the current dataset.

Parameters :

  • from : A date reference, in the unix GMT format, that will be shifted to to. See DateManager for date conversions. An empty string means the date of the first data point will become to.

  • to : The new date, in the unix GMT format, to apply at the previous from date. See DateManager for date conversions.

  • format : (Optional) The new date format to apply. See DateManager for the format list.

convertToSeconds

convertToSeconds{ }

On a non-dated dataset, this function will make the dataset dated, considering its X data as seconds.

get

get{ attribute }

Get an attribute of the dataset. See the list of attributes in the Dataset description.

Parameters :

  • attribute : The attribute name to fetch.

Return : The attribute value.

length

length

Get the dataset length, that is, its number of points.

Return : An integer representing the number of points.

removeLabels

removeLabels{ }

Remove all labels of the dataset. It will then be marked as a FLT dataset.

set

set{ attribute value }

Set an attribute of the dataset. See the list of attributes in the Dataset description.

Parameters :

  • attribute : The attribute name to set.

  • value : The value to set to the attribute.

setLabel

setLabel{ value label }

Set a label to display in place of a specific integer value.

Parameters :

  • value : The value to map to a label. It must be an integer value.

  • label : The label to display at the given value.

sort

sort{ }

Sort the dataset into chronological order.

spreadlabels

spreadlabels{ keepUnused }

Spread the labels by renumbering their raw values starting from the PrestoPlot BaseLabelOffset configuration value.

Parameters :

  • keepUnused : Indicates whether unused labels should be kept (default) or stripped.

x

x{ indexFrom indexTo }

Get one or more X values from this dataset. X values are generally dates in the PrestoPlot internal format (see DateManager). If you only give an index, the X value at this position is returned. The first value is the 0'th index. If you give both an index From and an index To, a list of all values between those indices (both included) is returned.

Parameters :

  • indexFrom : The first index to read.

  • indexTo : (Optional) The last index to read.

Return : An X value, or a list of X values.

y

y{ indexFrom indexTo }

Get one or more Y values from this dataset. If you only give an index, the Y value at this position is returned. The first value is the 0'th index. If you give both an index From and an index To, a list of all values between those indices (both included) is returned.

Parameters :

  • indexFrom : The first index to read.

  • indexTo : (Optional) The last index to read.

Return : A Y value, or a list of Y values.