azu / arsscale

[Objective-C] Porting D3.js Scales concepts to iOS.

ArsScale

Objective-C port of D3.js Scales.

• Support Linear scale.

Installation

pod 'ArsScale'

Usage

NSArray *dataArray = @[@1, @5, @10, @18, @22, @44, @55, @114];
ArsScaleLinear *scaleLinear = [[ArsScaleLinear alloc] init];
CGSize canvasSize = CGSizeMake(320, 480);
scaleLinear.domain = @[ArsMin(dataArray), ArsMax(dataArray)];
scaleLinear.range = @[@0, @(canvasSize.width)];
scaleLinear.clamp = YES;
scaleLinear.niceByStep([dataArray count]);
for (NSNumber *value in dataArray) {
    NSLog(@"Value:%@ , Scaled: %@", value, [scaleLinear scale:value]);
}
/*
Value:1 , Scaled: 2.666666666666667
Value:5 , Scaled: 13.33333333333333
Value:10 , Scaled: 26.66666666666666
Value:18 , Scaled: 48
Value:22 , Scaled: 58.66666666666666
Value:44 , Scaled: 117.3333333333333
Value:55 , Scaled: 146.6666666666667
Value:114 , Scaled: 304
*/
[linear ticks:10];
/* e.g) use for axis label
(
    0,
    10,
    20,
    30,
    40,
    50,
    60,
    70,
    80,
    90,
    100,
    110,
    120
)
*/

API

@interface ArsScaleLinear : ArsScale
// extend the scale domain to nice round numbers.
// @see https://github.com/mbostock/d3/wiki/Quantitative-Scales#wiki-linear_nice
// @example `linear.nice()`
- (void (^)(void))nice;

// @example `linear.niceByStep(10)`
- (void (^)(NSUInteger))niceByStep;

// enable or disable clamping of the output range.
// @see https://github.com/mbostock/d3/wiki/Quantitative-Scales#wiki-linear_clamp
@property(nonatomic, getter=isClamp) BOOL clamp;
#pragma mark - block
@property(nonatomic, copy) ArsInterpolate interpolate;
@property(nonatomic, copy) ArsUninterpolate uninterpolate;
#pragma mark - produce

- (NSNumber *)scale:(NSNumber *) number;

// invert scale
- (NSNumber *)invert:(NSNumber *) number;

#pragma mark - ticks
// returns approximately count representative values from the scale's input domain.
// @see https://github.com/mbostock/d3/wiki/Quantitative-Scales#wiki-linear_ticks
- (NSArray *)ticks:(NSUInteger)count;
@end

More Info

Very Nice article about D3.scale.

• Jerome Cukier » d3: scales, and color.

D3.js API Reference

• D3.js Scales

Example

• azu/LineChartOnRecycledScroll
  • LineChart
• azu/MultipleLineChart
  • Multiple LineChart
• azu/DrawLineLiz
  • BarPlot

Dependence

• azu/ArsDashFunction
  • Contain ArsMin, ArsMax, ArsRange etc...

Contributing

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am 'Add some feature'
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

License

3-clause BSD license

Acknowledgment

D3.js
https://github.com/mbostock/d3
Copyright (c) 2010-2014, Michael Bostock