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calc_histogram [2015/10/12 00:42] admin |
calc_histogram [2026/08/28 03:11] (current) hermann Sync from local documentation review |
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| ===== Description ===== | ===== Description ===== | ||
| - | This functor calculates a histogram from a map. | + | Calculates a histogram from a map. |
| ===== Inputs ===== | ===== Inputs ===== | ||
| - | ^ Name ^ Type ^ Description ^ | + | ^ Name ^ Type ^ Description ^ |
| - | | Map | [[Map Type]] | Any map | | + | | Map | [[Map Type]] | Any map. | |
| ===== Optional Inputs ===== | ===== Optional Inputs ===== | ||
| ^ Name ^ Type ^ Description ^ Default Value ^ | ^ Name ^ Type ^ Description ^ Default Value ^ | ||
| - | | Interval Width | [[Real Value Type]] | The width of the histogram interval. | 1.0 | | + | | Interval Width | [[Real Value Type]] | Width of each histogram interval (bin). | 1 | |
| - | | Cumulative | [[Boolean Value Type]] | If true, the calculated histogram is cumulative. | False | | + | | Cumulative | [[Boolean Value Type]] | If true, the calculated histogram is cumulative. | No | |
| - | | Relative | [[Boolean Value Type]] | If true, the values in the histogram are normalized by the total number of occurrences. | False | | + | | Relative | [[Boolean Value Type]] | If true, the values in the histogram are normalized by the total number of occurrences. | No | |
| ===== Outputs ===== | ===== Outputs ===== | ||
| ^ Name ^ Type ^ Description ^ | ^ Name ^ Type ^ Description ^ | ||
| - | | Histogram | [[Lookup Table Type|Lookup Table]] | The calculated histogram. | | + | | Histogram | [[Lookup Table Type]] | The calculated histogram. | |
| - | ===== Notes ===== | + | ===== Group ===== |
| - | It also possible to calculate a histogram relative to the cumulative values. To do this, set both input flags ("Cumulative" and "Relative"). | + | [[Functor List#Statistics | Statistics]] |
| - | When the "Interval Width" is different from one, the input values are remapped according to the expression below to speed up the calculation. | + | ===== Notes ===== |
| - | <m>value2 =delim{|}{value/width}{|}*width</m>, where //value2// is the resulting value, //value// is the value present in the input map and //width// is the "Interval Width". | + | Only the map's first layer is used to build the histogram. |
| - | Because of the remapping, the lower limit of the resulting histogram can be lower than the minimum value in the input map. The upper limit of the histogram can be greater than the maximum value in the input map. | + | Each key in the output table is the lower bound of an interval, obtained by rounding the corresponding cell value down to the nearest multiple of Interval Width; the associated value is the count of cells falling in that interval (or, if Relative is true, that count divided by the total number of non-null cells). Because of this rounding, the lowest and highest keys in the resulting table can fall outside the range of values actually present in Map. |
| - | ===== Group ===== | + | Setting both Cumulative and Relative produces a histogram of cumulative relative frequencies. |
| - | [[Functor List#Statistics|Statistics]] | + | Raises an error if Interval Width is not greater than 0. |
| ===== Internal Name ===== | ===== Internal Name ===== | ||