Description: getting data for building a chart from text file.
#import <Foundation/Foundation.h> #import "Charting/ChartDataSource.h" @interface DataSource : NSObject <ChartDataSource> { NSArray *_timestampTitles; NSArray *_timestampArray; double _yMin; double _yMax; double _xMin; double _xMax; double _minValue; double _maxValue; double _secondaryYMin; double _secondaryYMax; double _accumulatedMin; double _accumulatedMax; double _accumulatedSecondaryMin; double _accumulatedSecondaryMax; int seriesCount; NSMutableArray *legendTitles; NSMutableArray *data; int _currTimestamp; BOOL m_isBubble; } - (id) init; - (void ) loadData; @property (assign) int countSeries; - (void )obtainMin:(double *)min andMax:(double *)max fromArray:(NSArray *)arr addingPositivesTo:(NSMutableArray *)positiveValues addingNegativesTo:(NSMutableArray *)negativeValues; - (void )prepare; @end
#import "DataSource.h" @implementation DataSource @synthesize accumulatedMax = _accumulatedMax; @synthesize accumulatedMin = _accumulatedMin; @synthesize accumulatedSecondaryMax = _accumulatedSecondaryMax; @synthesize accumulatedSecondaryMin = _accumulatedSecondaryMin; @synthesize yMax = _yMax; @synthesize xMax = _xMax; @synthesize yMin = _yMin; @synthesize xMin = _xMin; @synthesize minValue = _minValue; @synthesize maxValue = _maxValue; @synthesize secondaryYMax = _secondaryYMax; @synthesize secondaryYMin = _secondaryYMin; @synthesize timestampArray = _timestampArray; @synthesize timestampTitles = _timestampTitles; @synthesize countSeries = seriesCount; @synthesize currentTimestamp = _currentTimestamp; - (id) init { self = [super init]; if(self) { _yMin = 0.0; _yMax = 0.0; _xMin = 0.0; _xMax = 0.0; _secondaryYMin = 0.0; _secondaryYMax = 0.0; _accumulatedMin = 0.0; _accumulatedMax = 0.0; _accumulatedSecondaryMin = 0.0; _accumulatedSecondaryMax = 0.0; legendTitles = [NSMutableArray new]; m_isBubble = YES; // Determine data array data = [NSMutableArray new]; [self loadData]; seriesCount = [data count]; return self; } return nil; } - (void )loadData { NSString *path = [[NSBundle mainBundle] pathForResource:@"data.txt" ofType:nil]; // Get path to data file NSString *dataString = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:nil]; // Read contents NSArray *lines = [dataString componentsSeparatedByString:@"\n"]; // Split string with contents into substrings and insert into array NSMutableArray *table = [NSMutableArray new]; for (NSString *line in lines) { [table addObject:[line componentsSeparatedByString:@";"]]; // Split each array element into substrings } NSMutableArray *timelineTitles = [[table objectAtIndex:0] mutableCopy]; [timelineTitles removeObjectAtIndex:0]; _timestampTitles = [[NSArray arrayWithArray:timelineTitles] retain]; _timestampArray = [[NSArray arrayWithArray:timelineTitles] retain]; [timelineTitles release]; // Insert data by each country into array for (int i = 1; i < [table count]; i++) { NSArray *line = [table objectAtIndex:i]; NSMutableArray *values = [[NSMutableArray new] autorelease]; [legendTitles addObject:[line objectAtIndex:0]]; for (int j = 1; j < [line count]; j++) { [values addObject:[NSNumber numberWithFloat:[[line objectAtIndex:j] floatValue]] ]; } [data addObject:values]; } } // Series data - (NSArray *) seriesDataWithIndex:(int)seriesIndex { NSString *num = [NSString stringWithFormat:@"%d",_currTimestamp]; int pos = [_timestampArray indexOfObject:num]; NSArray *series = [data objectAtIndex:seriesIndex]; if(m_isBubble) return [NSArray arrayWithObjects:[series objectAtIndex:0],[series objectAtIndex:1],[series objectAtIndex:1],[series objectAtIndex:1], nil]; else return series; } - (NSArray *)seriesDataWithIndex:(int)seriesIndex andTimestampValue:(int)timestamp { NSLog(@"%d",timestamp); NSString *num = [NSString stringWithFormat:@"%d",_currTimestamp]; int pos = [_timestampArray indexOfObject:num]; NSArray *series = [data objectAtIndex:seriesIndex]; int currTime = (timestamp-1) <0 ? 0: (timestamp - 1); if(m_isBubble) return [NSArray arrayWithObjects:[series objectAtIndex:currTime],[series objectAtIndex:currTime],[series objectAtIndex:currTime],[series objectAtIndex:currTime], nil]; else return series; } -(NSArray *)seriesDataWithSizeWithIndex:(int)seriesIndex andTimestampValue:(int)timestamp { NSString *num = [NSString stringWithFormat:@"%d",_currTimestamp]; int pos = [_timestampArray indexOfObject:num]; NSArray *series = [data objectAtIndex:seriesIndex]; int currTime = (timestamp - 1) <0 ? 0: (timestamp - 1); if(m_isBubble) return [NSArray arrayWithObjects:[series objectAtIndex:currTime],[series objectAtIndex:currTime],[series objectAtIndex:currTime],[series objectAtIndex:currTime], nil]; else return series; } // Determine series name displayed in legend - (NSString *)seriesNameWithIndex:(int)seriesIndex { return [legendTitles objectAtIndex:seriesIndex]; } // Calculate value of maximum and minimum elements in data - (void )obtainMin:(double *)min andMax:(double *)max fromArray:(NSArray *)arr addingPositivesTo:(NSMutableArray *)positiveValues addingNegativesTo:(NSMutableArray *)negativeValues { if(([positiveValues count] == 0) || ([negativeValues count] == 0) ) { [positiveValues removeAllObjects]; [negativeValues removeAllObjects]; for (int i=0; i < [arr count]; i++) { NSNumber *value = [arr objectAtIndex:i]; if ([value floatValue] > 0) { [positiveValues addObject:[arr objectAtIndex:i]]; } [positiveValues addObject:[NSNumber numberWithFloat:0.0f]]; } for (int i=0; i < [arr count]; i++) { NSNumber *value = [arr objectAtIndex:i]; if ([value floatValue] < 0) { [negativeValues addObject:[arr objectAtIndex:i]]; } [negativeValues addObject:[NSNumber numberWithFloat:0.0f]]; } } else { for (int i=0; i < [arr count]; i++) { NSNumber *value = [arr objectAtIndex:i]; if ([value floatValue] > 0) { NSNumber *num = [positiveValues objectAtIndex:i]; num = [NSNumber numberWithFloat:[num floatValue] + [value floatValue]]; [positiveValues replaceObjectAtIndex:i withObject:num]; } else { NSNumber *num = [negativeValues objectAtIndex:i]; num = [NSNumber numberWithFloat:[num floatValue] + [value floatValue]]; [negativeValues replaceObjectAtIndex:i withObject:num]; } } float _min = *min; float _max = *max; for (int i=0; i < [arr count]; i++) { NSNumber *value = [arr objectAtIndex:i]; if ([value floatValue] > _max) _max = [value floatValue]; if ([value floatValue] < _min) _min = [value floatValue]; } *max = _max; *min = _min; } } - (void )prepare { NSMutableArray *positive = [NSMutableArray new]; NSMutableArray *negative = [NSMutableArray new]; for(int i = 0; i < seriesCount ; i++) { [self obtainMin:&_yMin andMax:&_yMax fromArray:[self seriesDataWithIndex:i] addingPositivesTo:positive addingNegativesTo:negative]; } for (int i=0; i < [positive count]; i++) { NSNumber *value = [positive objectAtIndex:i]; if ([value floatValue] > _accumulatedMax ) { _accumulatedMax = [value floatValue]; _accumulatedSecondaryMax = [value floatValue]; } } for (int i=0; i < [negative count]; i++) { NSNumber *value = [negative objectAtIndex:i]; if ([value floatValue] < _accumulatedMax ) { _accumulatedMin = [value floatValue]; _accumulatedSecondaryMin = [value floatValue]; } } _xMax = _yMax; _xMin = _yMin; _secondaryYMax = _yMax; _secondaryYMin = _yMin; _maxValue = _yMax; _minValue = _yMin; [positive release]; [negative release]; } - (NSDictionary *) availableSeriesHeaders { return nil; } // Determine X axis label - (NSString *)xAxisNameForMask:(NSString *)mask { return @""; } // Determine Y axis label - (NSString *)yAxisNameForMask:(NSString *)mask { return @""; } // Determine secondary axis label - (NSString *)secondaryAxisNameForMask:(NSString *)mask { return @"Secondary axis"; } - (double )xMax { return _xMax; } - (double ) xMin { return _xMin; } - (double ) yMax { return _yMax; } - (double ) yMin { return _yMin; } - (double )secondaryYMin { return _secondaryYMin; } - (double )secondaryYMax { return _secondaryYMax; } - (double )accumulatedSecondaryMin { return _accumulatedSecondaryMin; } - (double )accumulatedSecondaryMax { return _accumulatedSecondaryMax; } - (int)minTimestamp { return 0; } - (int)maxTimestamp { return 0; } - (void )setMaxTimestamp:(int)mt { } - (void )setMinTimestamp:(int)mt { } - (void)setStartDataIndexOffset:(int)startOffset andEndDataIndexOffset:(int)endOffset { } @end
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