This tool extracts features from an input vector into an output file based on attribute properties. The user must specify the name of the input (--input
) and output (--output
) files, along with the filter statement (--statement
). The conditional statement is a single-line logical condition containing one or more attribute variables contained in the file's attribute table that evaluates to TRUE/FALSE. In addition to the common comparison and logical
operators, i.e. < > <= >= == (EQUAL TO) != (NOT EQUAL TO) || (OR) && (AND), conditional statements may contain a
any valid mathematical operation and the null
value.
Identifier | Argument Amount | Argument Types | Description | |
`min` | >= 1 | Numeric | Returns the minimum of the arguments | |
`max` | >= 1 | Numeric | Returns the maximum of the arguments | |
`len` | 1 | String/Tuple | Returns the character length of a string, or the amount of elements in a tuple (not recursively) | |
`floor` | 1 | Numeric | Returns the largest integer less than or equal to a number | |
`round` | 1 | Numeric | Returns the nearest integer to a number. Rounds half-way cases away from 0.0 | |
`ceil` | 1 | Numeric | Returns the smallest integer greater than or equal to a number | |
`if` | 3 | Boolean, Any, Any | If the first argument is true, returns the second argument, otherwise, returns the third | |
`contains` | 2 | Tuple, any non-tuple | Returns true if second argument exists in first tuple argument. | |
`contains_any` | 2 | Tuple, Tuple of any non-tuple | Returns true if one of the values in the second tuple argument exists in first tuple argument. | |
`typeof` | 1 | Any | returns "string", "float", "int", "boolean", "tuple", or "empty" depending on the type of the argument | |
`math::is_nan` | 1 | Numeric | Returns true if the argument is the floating-point value NaN, false if it is another floating-point value, and throws an error if it is not a number | |
`math::is_finite` | 1 | Numeric | Returns true if the argument is a finite floating-point number, false otherwise | |
`math::is_infinite` | 1 | Numeric | Returns true if the argument is an infinite floating-point number, false otherwise | |
`math::is_normal` | 1 | Numeric | Returns true if the argument is a floating-point number that is neither zero, infinite, [subnormal](https://en.wikipedia.org/wiki/Subnormal_number), or NaN, false otherwise | |
`math::ln` | 1 | Numeric | Returns the natural logarithm of the number | |
`math::log` | 2 | Numeric, Numeric | Returns the logarithm of the number with respect to an arbitrary base | |
`math::log2` | 1 | Numeric | Returns the base 2 logarithm of the number | |
`math::log10` | 1 | Numeric | Returns the base 10 logarithm of the number | |
`math::exp` | 1 | Numeric | Returns `e^(number)`, (the exponential function) | |
`math::exp2` | 1 | Numeric | Returns `2^(number)` | |
`math::pow` | 2 | Numeric, Numeric | Raises a number to the power of the other number | |
`math::cos` | 1 | Numeric | Computes the cosine of a number (in radians) | |
`math::acos` | 1 | Numeric | Computes the arccosine of a number. The return value is in radians in the range [0, pi] or NaN if the number is outside the range [-1, 1] | |
`math::cosh` | 1 | Numeric | Hyperbolic cosine function | |
`math::acosh` | 1 | Numeric | Inverse hyperbolic cosine function | |
`math::sin` | 1 | Numeric | Computes the sine of a number (in radians) | |
`math::asin` | 1 | Numeric | Computes the arcsine of a number. The return value is in radians in the range [-pi/2, pi/2] or NaN if the number is outside the range [-1, 1] | |
`math::sinh` | 1 | Numeric | Hyperbolic sine function | |
`math::asinh` | 1 | Numeric | Inverse hyperbolic sine function | |
`math::tan` | 1 | Numeric | Computes the tangent of a number (in radians) | |
`math::atan` | 1 | Numeric | Computes the arctangent of a number. The return value is in radians in the range [-pi/2, pi/2] | |
`math::atan2` | 2 | Numeric, Numeric | Computes the four quadrant arctangent in radians | |
`math::tanh` | 1 | Numeric | Hyperbolic tangent function | |
`math::atanh` | 1 | Numeric | Inverse hyperbolic tangent function. | |
`math::sqrt` | 1 | Numeric | Returns the square root of a number. Returns NaN for a negative number | |
`math::cbrt` | 1 | Numeric | Returns the cube root of a number | |
`math::hypot` | 2 | Numeric | Calculates the length of the hypotenuse of a right-angle triangle given legs of length given by the two arguments | |
`math::abs` | 1 | Numeric | Returns the absolute value of a number, returning an integer if the argument was an integer, and a float otherwise | |
`str::regex_matches` | 2 | String, String | Returns true if the first argument matches the regex in the second argument (Requires `regex_support` feature flag) | |
`str::regex_replace` | 3 | String, String, String | Returns the first argument with all matches of the regex in the second argument replaced by the third argument (Requires `regex_support` feature flag) | |
`str::to_lowercase` | 1 | String | Returns the lower-case version of the string | |
`str::to_uppercase` | 1 | String | Returns the upper-case version of the string | |
`str::trim` | 1 | String | Strips whitespace from the start and the end of the string | |
`str::from` | >= 0 | Any | Returns passed value as string | |
`bitand` | 2 | Int | Computes the bitwise and of the given integers | |
`bitor` | 2 | Int | Computes the bitwise or of the given integers | |
`bitxor` | 2 | Int | Computes the bitwise xor of the given integers | |
`bitnot` | 1 | Int | Computes the bitwise not of the given integer | |
`shl` | 2 | Int | Computes the given integer bitwise shifted left by the other given integer | |
`shr` | 2 | Int | Computes the given integer bitwise shifted right by the other given integer | |
`random` | 0 | Empty | Return a random float between 0 and 1. Requires the `rand` feature flag. | |
`pi` | 0 | Empty | Return the value of the PI constant. | / |
The following are examples of valid conditional statements:
HEIGHT >= 300.0
CROP == "corn"
(ELEV >= 525.0) && (HGT_AB_GR <= 5.0)
math::ln(CARBON) > 1.0
VALUE == null
def extract_by_attribute(self, input: Vector, statement: str) -> Vector: ...