readers.text¶
The text reader reads data from ASCII text files. Each point is represented in the file as a single line. Each line is expected to be divided into a number of fields by a separator. Each field represents a value for a point’s dimension. Each value needs to be formatted properly for C++ language double-precision values.
The text reader expects a header line to indicate the dimensions are in each subsequent line. There are two types of header lines.
Quoted dimension names¶
When the first character of the header is a double quote, each dimension name is assumed to be surrounded by double quotes. Any text following a quoted dimension name and the start of the next dimension name is ignored. The separator option can’t be used with quoted dimension names.
Unquoted dimension names¶
The first non alpha-numeric character encountered is treated as a separator between dimension names. The separator in the header line can be overridden by the separator option.
Each line in the file must contain the same number of fields as indicated by dimension names in the header. Spaces are generally ignored in the input unless used as a separator. When a space character is used as a separator, any number of consecutive spaces are treated as single space and leading/trailing spaces are ignored.
Blank lines are ignored after the header line is read.
Streamable Stage
This stage supports streaming operations
Example Input File¶
This input file contains X, Y and Z value for 10 points.
X,Y,Z
289814.15,4320978.61,170.76
289814.64,4320978.84,170.76
289815.12,4320979.06,170.75
289815.60,4320979.28,170.74
289816.08,4320979.50,170.68
289816.56,4320979.71,170.66
289817.03,4320979.92,170.63
289817.53,4320980.16,170.62
289818.01,4320980.38,170.61
289818.50,4320980.59,170.58
Example #1¶
[
{
"type":"readers.text",
"filename":"inputfile.txt"
},
{
"type":"writers.text",
"filename":"outputfile.txt"
}
]
Example #2¶
This reads the data in the input file as Red, Green and Blue instead of as X, Y and Z.
[
{
"type":"readers.text",
"filename":"inputfile.txt",
"header":"Red, Green, Blue",
"skip":1
},
{
"type":"writers.text",
"filename":"outputfile.txt"
}
]
Options¶
- filename
- text file to read [Required]
- count
- Maximum number of points to read. [Default: unlimited]
- override_srs
- Spatial reference to apply to the data. Overrides any SRS in the input itself. Can be specified as a WKT, proj.4 or EPSG string. [Default: none]
- header
- String to use as the file header. All lines in the file are assumed to be records containing point data unless skipped with the skip option. [Default: None]
- separator
- Separator character to override that found in header line. [Default: None]
- skip
- Number of lines to ignore at the beginning of the file. [Default: 0]