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jqr (version 1.3.5)

maths: Math operations

Description

Math operations

Usage

do(.data, ...)

do_(.data, ..., .dots)

lengthj(.data)

sqrtj(.data)

floorj(.data)

minj(.data, ...)

minj_(.data, ..., .dots)

maxj(.data, ...)

maxj_(.data, ..., .dots)

ad(.data)

map(.data, ...)

map_(.data, ..., .dots)

Arguments

.data

input. This can be JSON input, or an object of class jqr that has JSON and query params combined, which is passed from function to function when using the jqr DSL.

...

Comma separated list of unquoted variable names

.dots

Used to work around non-standard evaluation

dots

dots

Examples

Run this code
# do math
jq('{"a": 7}', '.a + 1')
# adding null gives back same result
jq('{"a": 7}', '.a + null')
jq('{"a": 7}', '.a += 1')
'{"a": 7}' %>%  do(.a + 1)
# '{"a": 7}' %>%  do(.a += 1) # this doesn't work quite yet
'{"a": [1,2], "b": [3,4]}' %>%  do(.a + .b)
'{"a": [1,2], "b": [3,4]}' %>%  do(.a - .b)
'{"a": 3}' %>%  do(4 - .a)
'["xml", "yaml", "json"]' %>%  do('. - ["xml", "yaml"]')
'5' %>%  do(10 / . * 3)
## many JSON inputs
'{"a": [1,2], "b": [3,4]} {"a": [1,5], "b": [3,10]}' %>%  do(.a + .b)

# comparisons
'[5,4,2,7]' %>% index() %>% do(. < 4)
'[5,4,2,7]' %>% index() %>% do(. > 4)
'[5,4,2,7]' %>% index() %>% do(. <= 4)
'[5,4,2,7]' %>% index() %>% do(. >= 4)
'[5,4,2,7]' %>% index() %>% do(. == 4)
'[5,4,2,7]' %>% index() %>% do(. != 4)
## many JSON inputs
'[5,4,2,7] [4,3,200,0.1]' %>% index() %>% do(. < 4)

# length
'[[1,2], "string", {"a":2}, null]' %>% index %>% lengthj

# sqrt
'9' %>% sqrtj
## many JSON inputs
'9 4 5' %>% sqrtj

# floor
'3.14159' %>% floorj
## many JSON inputs
'3.14159 30.14 45.9' %>% floorj

# find minimum
'[5,4,2,7]' %>% minj
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% minj
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% minj(foo)
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% minj(bar)
## many JSON inputs
'[{"foo":1}, {"foo":14}] [{"foo":2}, {"foo":3}]' %>% minj(foo)

# find maximum
'[5,4,2,7]' %>% maxj
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% maxj
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% maxj(foo)
'[{"foo":1, "bar":14}, {"foo":2, "bar":3}]' %>% maxj(bar)
## many JSON inputs
'[{"foo":1}, {"foo":14}] [{"foo":2}, {"foo":3}]' %>% maxj(foo)

# increment values
## requires special % operators, they get escaped internally
'{"foo": 1}' %>% do(.foo %+=% 1)
'{"foo": 1}' %>% do(.foo %-=% 1)
'{"foo": 1}' %>% do(.foo %*=% 4)
'{"foo": 1}' %>% do(.foo %/=% 10)
'{"foo": 1}' %>% do(.foo %//=% 10)
### fix me - %= doesn't work
# '{"foo": 1}' %>% do(.foo %%=% 10)
## many JSON inputs
'{"foo": 1} {"foo": 2} {"foo": 3}' %>% do(.foo %+=% 1)

# add
'["a","b","c"]' %>% ad
'[1, 2, 3]' %>% ad
'[]' %>% ad
## many JSON inputs
'["a","b","c"] ["d","e","f"]' %>% ad

# map
## as far as I know, this only works with numbers, thus it's
## in the maths section
'[1, 2, 3]' %>% map(.+1)
'[1, 2, 3]' %>% map(./1)
'[1, 2, 3]' %>% map(.*4)
# many JSON inputs
'[1, 2, 3] [100, 200, 300] [1000, 2000, 30000]' %>% map(.+1)

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