Add support for horizontal and vertical limits

Author: ruivieira

docs/README.md

@@ -183,3 +183,22 @@ for n in 0..<9:
 ```
 
 ![plot](grid.png)
+
+### horizontal and vertical limits
+
+```nim
+let x10 = rnorm(1000, 0.0, 2.0)
+let y10 = rnorm(1000, 0.0, 2.0)
+let figure10 = newFigure()
+figure10.size = (8.0, 4.0)
+figure10.grid = (1, 2)
+let sp10 = newScatterPlot(x10, y10)
+figure10.add newXLimit(0.0, 1.0)
+figure10.add sp10
+figure10.subplot
+figure10.add newYLimit(-1.0, 0.0)
+figure10.add sp10
+figure10.save("docs/limits.png")
+```
+
+![plot](limits.png)

docs/examples.nim

@@ -119,3 +119,17 @@ for n in 0..<9:
     lp.colour = "red"
     figure9.add lp
 figure9.save("docs/grid.png")
+
+### horizontal and vertical limits
+let x10 = rnorm(1000, 0.0, 2.0)
+let y10 = rnorm(1000, 0.0, 2.0)
+let figure10 = newFigure()
+figure10.size = (8.0, 4.0)
+figure10.grid = (1, 2)
+let sp10 = newScatterPlot(x10, y10)
+figure10.add newXLimit(0.0, 1.0)
+figure10.add sp10
+figure10.subplot
+figure10.add newYLimit(-1.0, 0.0)
+figure10.add sp10
+figure10.save("docs/limits.png")

docs/limits.png

@@ -231,4 +231,23 @@ method render[A,B](this: Annotation[A,B]): string =
     return &"ax=plt.gca()\nax.annotate('{this.text}', xy=({this.x}, {this.y}))"
 
 proc newAnnotation*[A,B](x: A, y: B, text: string): Annotation[A,B] =
-  Annotation[A,B](x: x, y: y, text: text, colour: "")
+  Annotation[A,B](x: x, y: y, text: text, colour: "")
+
+# Limits
+type XLimit[A] = ref object of Plot
+  min: A
+  max: A
+method render[A](this: XLimit[A]): string =
+  return &"ax=plt.gca()\nax.set_xlim([{this.min},{this.max}])"
+
+proc newXLimit*[A](min: A, max: A): XLimit[A] = 
+  XLimit[A](min: min, max: max)
+
+type YLimit[A] = ref object of Plot
+  min: A
+  max: A
+method render[A](this: YLimit[A]): string =
+  return &"ax=plt.gca()\nax.set_ylim([{this.min},{this.max}])"
+
+proc newYLimit*[A](min: A, max: A): YLimit[A] = 
+  YLimit[A](min: min, max: max)