// NewErrorPoints returns a new ErrorPoints where each
// point in the ErrorPoints is given by evaluating the
// center function on the Xs and Ys for the corresponding
// set of XY values in the pts parameter. The XError
// and YError are computed likewise, using the err
// function.
//
// This function can be useful for summarizing sets of
// scatter points using a single point and error bars for
// each element of the scatter.
func NewErrorPoints(f func([]float64) (c, l, h float64), pts ...plotter.XYer) (*ErrorPoints, error) {
c := &ErrorPoints{
XYs: make(plotter.XYs, len(pts)),
XErrors: make(plotter.XErrors, len(pts)),
YErrors: make(plotter.YErrors, len(pts)),
}
for i, xy := range pts {
xs := make([]float64, xy.Len())
ys := make([]float64, xy.Len())
for j := 0; j < xy.Len(); j++ {
xs[j], ys[j] = xy.XY(j)
if err := plotter.CheckFloats(xs[j], ys[j]); err != nil {
return nil, err
}
}
c.XYs[i].X, c.XErrors[i].Low, c.XErrors[i].High = f(xs)
if err := plotter.CheckFloats(c.XYs[i].X, c.XErrors[i].Low, c.XErrors[i].High); err != nil {
return nil, err
}
c.XYs[i].Y, c.YErrors[i].Low, c.YErrors[i].High = f(ys)
if err := plotter.CheckFloats(c.XYs[i].Y, c.YErrors[i].Low, c.YErrors[i].High); err != nil {
return nil, err
}
}
return c, nil
}
func NewErrorPointsXSpaced(f func([]float64) (c, l, h float64),
howManyPoints, howManyErrorBars int64,
dataRange Float64Range,
pointsGenerators []PointGenerator) (*[]PointsAndErrorPoints, error) {
if howManyPoints < 2 {
panic("NewErrorPointsXSpaced: only 2 or more points can be used")
}
dataMin := dataRange.min
dataMax := dataRange.max
ptsNerrs := make([]PointsAndErrorPoints, len(pointsGenerators))
//Figure out where the data points go
xIncr := (dataMax - dataMin) / (float64(howManyPoints) - 1.0)
for curGeneratorIndex, pointsGenerator := range pointsGenerators {
//create and instantiate the PointsAndErrorPoints object
points := make(plotter.XYs, howManyPoints)
ptsNerrs[curGeneratorIndex].points = &points
errorPoints := ErrorPoints{
XYs: make(plotter.XYs, howManyErrorBars),
XErrors: make(plotter.XErrors, howManyErrorBars),
YErrors: make(plotter.YErrors, howManyErrorBars),
}
ptsNerrs[curGeneratorIndex].errorPoints = &errorPoints
//rename a few things for ease of reading the code
genRangeMin := pointsGenerator.pointRange.min
genRangeMax := pointsGenerator.pointRange.max
generator := pointsGenerator.generator
//start by generating the data points that will define the line
ptsAdded := 0
for curX := dataMin; ptsAdded < points.Len() && curX <= dataMax+xIncr; curX += xIncr {
//if the current x value is outside of the generator range skip it
if curX < genRangeMin || curX > genRangeMax {
continue
}
//make sure that the x value we're going to use is okay
if err := plotter.CheckFloats(curX); err != nil {
return nil, err
}
//generate the set of y values at this given x value
ys := generator(curX)
//make sure that all the y values returned are okay
if err := plotter.CheckFloats(ys...); err != nil {
return nil, err
}
//set the x value for this point
points[ptsAdded].X = curX
//set the y value for this point as returned by this function
//we only want the points so ignore the range-type of data also returned
points[ptsAdded].Y, _, _ = f(ys)
//make sure that the returned value is okay
if err := plotter.CheckFloats(points[ptsAdded].Y); err != nil {
return nil, err
}
//We need to keep track of how many points we're actually adding
//because not all the x's will fall within the generators range
//and we might have to shrink the array to avoid problems when plotting
ptsAdded++
}
points = points[0:ptsAdded]
//Now figure out where the error bars go
xIncr = (dataMax - dataMin) / float64(howManyErrorBars)
//we want to space out the error bars so they don't all overlap
xOffset := (xIncr / 4.0) + float64(curGeneratorIndex)*(xIncr/2.0)/float64(len(pointsGenerators))
numErrsAdded := 0
for curX := dataMin; numErrsAdded < errorPoints.XYs.Len() && curX <= dataMax+xIncr; curX += xIncr {
x := curX + xOffset
if curX < genRangeMin || curX > genRangeMax || x < genRangeMin || x > genRangeMax {
continue
}
if err := plotter.CheckFloats(x); err != nil {
return nil, err
}
ys := generator(x)
if err := plotter.CheckFloats(ys...); err != nil {
return nil, err
}
errorPoints.XYs[numErrsAdded].X = x
errorPoints.XErrors[numErrsAdded].Low = 0.0
errorPoints.XErrors[numErrsAdded].High = 0.0
y, low, high := f(ys)
errorPoints.XYs[numErrsAdded].Y = y
errorPoints.YErrors[numErrsAdded].Low = low
errorPoints.YErrors[numErrsAdded].High = high
if err := plotter.CheckFloats(errorPoints.YErrors[numErrsAdded].Low, errorPoints.YErrors[numErrsAdded].High); err != nil {
return nil, err
}
numErrsAdded++
}
ptsNerrs[curGeneratorIndex].errorPoints.XYs = errorPoints.XYs[0:numErrsAdded]
ptsNerrs[curGeneratorIndex].errorPoints.XErrors = errorPoints.XErrors[0:numErrsAdded]
ptsNerrs[curGeneratorIndex].errorPoints.YErrors = errorPoints.YErrors[0:numErrsAdded]
}
return &ptsNerrs, nil
}
func NewErrorPointsSpaced(f func([]float64) (c, l, h float64),
pointSet, totalNumberOfPointSets,
howManyPoints, howManyErrorBars int64,
minX, maxX float64,
pointsGenerator func(float64) []float64,
minRange, maxRange float64) (*plotter.XYs, *ErrorPoints, error) {
if howManyPoints < 2 {
panic("NewErrorPointsXSpaced: only 2 or more points can be used")
}
points := make(plotter.XYs, howManyPoints)
errorBars := &ErrorPoints{
XYs: make(plotter.XYs, howManyErrorBars),
XErrors: make(plotter.XErrors, howManyErrorBars),
YErrors: make(plotter.YErrors, howManyErrorBars),
}
//generate the points first
xIncr := (maxX - minX) / (float64(howManyPoints) - 1.0)
i := 0
for curX := minX; i < points.Len() && curX <= maxX+xIncr; curX += xIncr {
if curX < minRange || curX > maxRange {
continue
}
if err := plotter.CheckFloats(curX); err != nil {
return nil, nil, err
}
ys := pointsGenerator(curX)
for j := 0; j < len(ys); j++ {
if err := plotter.CheckFloats(ys[j]); err != nil {
return nil, nil, err
}
}
points[i].X = curX
points[i].Y, _, _ = f(ys)
if err := plotter.CheckFloats(points[i].Y); err != nil {
return nil, nil, err
}
i++
}
points = points[0:i]
//generate the error bars
xIncr = (maxX - minX) / float64(howManyErrorBars)
xOffset := (xIncr / 4.0) + float64(pointSet)*(xIncr/2.0)/float64(totalNumberOfPointSets)
i = 0
for curX := minX; i < errorBars.XYs.Len() && curX <= maxX+xIncr; curX += xIncr {
x := curX + xOffset
if curX < minRange || curX > maxRange || x < minRange || x > maxRange {
continue
}
if err := plotter.CheckFloats(x); err != nil {
return nil, nil, err
}
ys := pointsGenerator(x)
for j := 0; j < len(ys); j++ {
if err := plotter.CheckFloats(ys[j]); err != nil {
return nil, nil, err
}
}
errorBars.XYs[i].X, errorBars.XErrors[i].Low, errorBars.XErrors[i].High = x, 0.0, 0.0
errorBars.XYs[i].Y, errorBars.YErrors[i].Low, errorBars.YErrors[i].High = f(ys)
if err := plotter.CheckFloats(errorBars.YErrors[i].Low, errorBars.YErrors[i].High); err != nil {
return nil, nil, err
}
i++
}
errorBars.XYs = errorBars.XYs[0:i]
errorBars.XErrors = errorBars.XErrors[0:i]
errorBars.YErrors = errorBars.YErrors[0:i]
return &points, errorBars, nil
}
