debug.type.changes

Returns a data frame for each variable in the execution containing the instances where the data type changed.

Each data frame contains the following columns:

• value The value of the variable.
• container The type of the container of the variable.
• dimension The size of the container.
• type The data type(s) contained within the container.
• code The line of code associated with the variable.
• scriptNum The script number associated with the variable.
• scriptName The name of the script associated with the variable.
• startLine The line number associated with the variable.

Usage

The function signature for debug.type.changes is:

debug.type.changes(...)

The parameter of this function is:

• var Optional. Variable name(s) to be queried. If variables are given (not NULL), the results will be filtered to show only those with the given variable name.

This function may be called only after initialising the debugger using either prov.debug, prov.debug.run, or prov.debug.file. For example:

prov.debug.run("myScript.R")
debug.type.changes()
debug.type.changes(x)
debug.type.changes("a", "b")

Output Examples

Let myScript.R be the following:

a <- "one"
a <- "two"
a <- 1L
a <- 2L

b <- 3L
b <- "three"

cc <- c(1:3)
cc <- TRUE

1. Checking for type changes in all variables

The result for debug.type.changes() is:

$a
  value container dimension      type       code scriptNum scriptName startLine
1 "two"    vector         1 character a <- "two"         1 myScript.R         2
2     1    vector         1   integer    a <- 1L         1 myScript.R         3

$b
    value container dimension      type         code scriptNum scriptName startLine
1       3    vector         1   integer      b <- 3L         1 myScript.R         6
2 "three"    vector         1 character b <- "three"         1 myScript.R         7

$cc
  value container dimension    type         code scriptNum scriptName startLine
1 1 2 3    vector         3 integer cc <- c(1:3)         1 myScript.R         9
2  TRUE    vector         1 logical   cc <- TRUE         1 myScript.R        10

Lines 1 and 4 are omitted as there are no type changes to variable a to and from those lines.

2. Checking for type changes in certain variables

By using the parameter var, the results may be filtered to be from only the queried variables.

For example, the result for debug.variable(a) is:

$a
  value container dimension      type       code scriptNum scriptName startLine
1 "two"    vector         1 character a <- "two"         1 myScript.R         2
2     1    vector         1   integer    a <- 1L         1 myScript.R         3

Similarly, the result for debug.variable("a", "cc") is:

$a
  value container dimension      type       code scriptNum scriptName startLine
1 "two"    vector         1 character a <- "two"         1 myScript.R         2
2     1    vector         1   integer    a <- 1L         1 myScript.R         3

$cc
  value container dimension    type         code scriptNum scriptName startLine
1 1 2 3    vector         3 integer cc <- c(1:3)         1 myScript.R         9
2  TRUE    vector         1 logical   cc <- TRUE         1 myScript.R        10