PHIGURE represents single or multiple statistical data as histograms consisting of a series of vertical or horizontal bars.
Single statistical data (represented by type C tsingle_data) consists of a series of names associated with values. This type of data may be represented using the thistog_single_x and thistog_single_y functions.
Multiple statistical data (represented by type C tmultiple_data) consists of a matrix of values arranged in a table with a certain number of rows and columns, associated with a list of names of columns and a list of names of rows. This type of data may be represented using the thistog_stack_x, thistog_stack_y, thistog_cluster_x, thistog_cluster_y, thistog_percent_x and thistog_percent_y functions.
Attribute functions may be used to modify histogram parameters : name spellings, values and sums of values, and spacing between bars as well as to append a character string to values, if necessary :
tset_histog_values presentation of histogram values.
tset_histog_names presentation of histogram names.
tset_histog_sums presentation of the sum of histogram values.
tset_histog_space histogram bar spacing.
tset_histog_append_string appending character strings to histogram values.
tset_histog_xxx functions must be called before thistog_xxx functions so that these attributes will be taken into account in displaying the data. These attributes are stored in the PHIGS structure used by the tset_histog_xxx functions and are read in that structure by tset_histog_xxx functions. If the tset_histog_xxx functions are not called, attribute default values are used.
C types specific to histogram functions are as follows :
typedef struct {
Pint num_values;
Pfloat *values;
char **names;
} Tsingle_data;
typedef struct {
Pint num_row, num_col;
Pfloat *values;
char **row_names, **col_names;
} Tmultiple_data;
typedef enum {
TRELATIVE_SPACE,
TABSOLUTE_SPACE
} Tspace_flag;
typedef enum {
THISTOG_ROW_COL,
THISTOG_COL_ROW
} Thistog_path;