xautorange and yautorange attributes


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Manual page for xautorange_and_yautorange_attributes(PL)

USAGE

xautorange: datafield=dfields other subattributes..
or..
yautorange: datafield=dfields other subattributes..

DESCRIPTION

xautorange and yautorange are attributes of proc areadef that allow the plot range to be determined by the range of data. Because this attribute is fairly involved, it has a manual page of its own.

Default autorange behavior is as follows: For numeric data the range is set to the nearest whole high and low scale increments that encompass the min and max of the data. For date and time data the range is set to the exact min and max of the data.

SUBATTRIBUTES

datafield=dfields

The only subattribute that must be specified is datafield=dfields. The dfields will be scanned to automatically find minima and maxima, and the range (either x or y) will be set accordingly. dfields may be a single dfield or a comma-delimited list of several dfields with no embedded space. Invalid or non-existant dfields will be silently ignored, but there must be at least one valid dfield. [Field list new in version 1.41; contributed by Paul Totten.]

The following subattributes allow autorange behavior to be controlled explicitly:

incmult=h

controls the amount of margin at high and low end when working with numeric data in default mode as described above. The default h is 1.0. The scale increment will be multiplied by h before determining the range. The low end of the range will not dip below zero if data are all positive. Probably should not be used with any other subattributes except datafield=. New in version 1.40.

nearest=s

may be used to explicitly define the extent of the range, to a boundary corresponding to a round value of your choice. If you do not specify a nearest= value autorange will guess based on the magnitude of the data. If nearest=exact is specified, the range will be the exact minima to the exact maxima. See the table below for some possible values for s. An example: if s is 100, and the data range from 23 to 1162, the plot's range will be 0 to 1200. The following illustrates some possible values for nearest=s:

s         range min and max will be set to:
-------   ---------------------------------
10        the nearest multiple of 10
0.1       the nearest multiple of 0.1
month     the nearest month boundary (date or datetime scaletypes only)
quarter   the nearest quarter-year boundary (date or datetime only)
year      the nearest year boundary (date or datetime only)
hour      the nearest hour boundary (time or datetime only)
day       the nearest day boundary (datetime only)
exact     the exact minima and maxima
(none)    a reasonable default (numeric data only)

margin=m

If specified, m basic units will be added to the maxima and also subtracted from the minima, before considering nearest. This may be used to guarantee margins at each end of the range. (Basic units are days for date and datetime scaletypes; and minutes for time.)

lowfix=lowval

If specified, the minima will always be lowval. This is useful when you want only the maxima to be automatically set based on data. (Introduced in version 1.3)

hifix=hival

If specified, the maxima will always be hival. This is useful when you want only the minima to be automatically set based on data. (Introduced in version 1.3)

format=printfspec

For very small numbers this subattribute may be useful, since normally values are rounded to six decimal places (introduced in version 1.34).

Example: xautorange: datafield=2 nearest=month margin=31

Example: yautorange: datafield=3,4,5,6,7

Some gallery examples where xautorange is used: qual , hitcount , and milltest


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Copyright Steve Grubb


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