Point Cloud Attribute Calculator
- Author: V. Wichmann (c) 2010-2013
- Menu: Shapes | Point Clouds | Tools
Description
The tool allows one to calculate a new attribute value per point, based on existing attributes of that point and a mathematical expression. Attribute fields are addressed by the character 'f' (for 'field') followed by the field number (i.e.: f1, f2, ..., fn) or by the field name in square brackets (e.g.: [Field Name]). Examples: sin(f1) * f2 + f3 [intensity] / 1000 The following operators are available for the formula definition:
| + | Addition |
| - | Subtraction |
| * | Multiplication |
| / | Division |
| abs(x) | Absolute Value |
| mod(x, y) | Returns the floating point remainder of x/y |
| int(x) | Returns the integer part of floating point value x |
| sqr(x) | Square |
| sqrt(x) | Square Root |
| exp(x) | Exponential |
| pow(x, y) | Returns x raised to the power of y |
| x ^ y | Returns x raised to the power of y |
| ln(x) | Natural Logarithm |
| log(x) | Base 10 Logarithm |
| pi() | Returns the value of Pi |
| sin(x) | Sine, expects radians |
| cos(x) | Cosine, expects radians |
| tan(x) | Tangent, expects radians |
| asin(x) | Arcsine, returns radians |
| acos(x) | Arccosine, returns radians |
| atan(x) | Arctangent, returns radians |
| atan2(x, y) | Arctangent of x/y, returns radians |
| min(x, y) | Returns the minimum of values x and y |
| max(x, y) | Returns the maximum of values x and y |
| gt(x, y) | Returns true (1), if x is greater than y, else false (0) |
| x > y | Returns true (1), if x is greater than y, else false (0) |
| lt(x, y) | Returns true (1), if x is less than y, else false (0) |
| x < y | Returns true (1), if x is less than y, else false (0) |
| eq(x, y) | Returns true (1), if x equals y, else false (0) |
| x = y | Returns true (1), if x equals y, else false (0) |
| and(x, y) | Returns true (1), if both x and y are true (i.e. not 0) |
| or(x, y) | Returns true (1), if at least one of both x and y is true (i.e. not 0) |
| ifelse(c, x, y) | Returns x, if condition c is true (i.e. not 0), else y |
| rand_u(x, y) | Random number, uniform distribution with minimum x and maximum y |
| rand_g(x, y) | Random number, Gaussian distribution with mean x and standard deviation y |
Parameters
| Name | Type | Identifier | Description | Constraints | |
|---|---|---|---|---|---|
| Input | Point Cloud | point cloud, input | PC_IN | Input point cloud. | - |
| Output | Result | point cloud, output, optional | PC_OUT | Output point cloud. | - |
| Options | Formula | text | FORMULA | - | Default: f1+f2 |
| Output Field Name | text | NAME | - | Default: Calculation | |
| Take Formula | boolean | FNAME | - | Default: 0 | |
| Data Type | data type | TYPE | Choose the data type of the output attribute. | Available Choices: [0] bit [1] unsigned 1 byte integer [2] signed 1 byte integer [3] unsigned 2 byte integer [4] signed 2 byte integer [5] unsigned 4 byte integer [6] signed 4 byte integer [7] unsigned 8 byte integer [8] signed 8 byte integer [9] 4 byte floating point number [10] 8 byte floating point number Default: 9 | |
| Use NoData | boolean | USE_NODATA | Include NoData values in the calculation. A typical application is the use of an ifelse() statement on NoData values. | Default: 0 |
Command Line
Usage: saga_cmd pointcloud_tools 10 [-PC_IN] [-PC_OUT ] [-FORMULA ] [-NAME ] [-FNAME ] [-TYPE ] [-USE_NODATA ] -PC_IN: Point Cloud point cloud, input -PC_OUT: Result point cloud, output, optional -FORMULA: Formula text Default: f1+f2 -NAME: Output Field Name text Default: Calculation -FNAME: Take Formula boolean Default: 0 -TYPE: Data Type data type Available Choices: [0] bit [1] unsigned 1 byte integer [2] signed 1 byte integer [3] unsigned 2 byte integer [4] signed 2 byte integer [5] unsigned 4 byte integer [6] signed 4 byte integer [7] unsigned 8 byte integer [8] signed 8 byte integer [9] 4 byte floating point number [10] 8 byte floating point number Default: 9 -USE_NODATA: Use NoData boolean Default: 0