Data
PromptBeginner5 minmarkdownQuality: 28
- subset argument uses non-standard evaluation — column names are resolved in the data frame
which can silently pick up wrong variables in programmatic use. Use [ with explicit logic in functions.
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Showing 24 of 131,462Categories: Data & Insights, General, Communication, Data, Cursor-rules, Coding & Debugging
Data
PromptBeginner5 minmarkdownQuality: 24
- Matrix indexing a data frame (`df[cbind(i
j)]`) coerces to matrix first — avoid.
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Data
PromptBeginner5 minmarkdownQuality: 28
- Data frame [ with single column: `df[
1]` returns a vector (drop=TRUE default for columns)
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Coding & Debugging
PromptBeginner5 minmarkdownQuality: 28
- Factor indexing: x[f] uses integer codes of factor f
not its character labels. Use x[as.character(f)] for label-based indexing.
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General
PromptBeginner5 minmarkdownQuality: 24
- `m[j = 2
i = 1] is m[2
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General
PromptBeginner5 minmarkdownQuality: 24
Non-obvious behaviors
gotchas
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General
PromptBeginner5 minmarkdownQuality: 28
- stl requires s.window (seasonal window) — must be specified
no default. s.window = periodic assumes fixed seasonality.
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General
PromptBeginner5 minmarkdownQuality: 24
- stl result components: $time.series matrix with columns seasonal
trend
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General
PromptBeginner5 minmarkdownQuality: 24
- decompose: simpler than stl
uses moving averages. type = additive or multiplicative.
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General
PromptBeginner5 minmarkdownQuality: 24
- `arima(x
order = c(p
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General
PromptBeginner5 minmarkdownQuality: 24
- vignette() lists all vignettes; `vignette(name
package = pkg)` opens a specific one.
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Data
PromptBeginner5 minmarkdownQuality: 24
- `ts(data
start
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General
PromptBeginner5 minmarkdownQuality: 24
- `format(object.size(x)
units = MB)` for human-readable output.
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General
PromptBeginner5 minmarkdownQuality: 24
- Update with `setTxtProgressBar(pb
value). Close with close(pb)`.
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General
PromptBeginner5 minmarkdownQuality: 24
- Style 1: rotating |/-\
style 2: simple progress. Only style 3 shows percentage.
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General
PromptBeginner5 minmarkdownQuality: 24
- Works with factors
matrices
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General
PromptBeginner5 minmarkdownQuality: 24
- `txtProgressBar(min
max
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Data
PromptBeginner5 minmarkdownQuality: 24
- `relist(flesh
skeleton) — flesh` is the flat data
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General
PromptBeginner5 minmarkdownQuality: 28
- Does add new names not in x — it uses x[names(val)] <- val internally
so any name in val gets added or replaced.
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General
PromptBeginner5 minmarkdownQuality: 28
- Inverse of unlist: given a flat vector and a skeleton list
reconstructs the nested structure.
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General
PromptBeginner5 minmarkdownQuality: 24
- `modifyList(x
val) replaces elements of list x with those in val` by name.
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General
PromptBeginner5 minmarkdownQuality: 24
- Checks attributes
names
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General
PromptBeginner5 minmarkdownQuality: 24
- FUN argument applies a function to each combination: `combn(5
3
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General
PromptBeginner5 minmarkdownQuality: 24
- `combn(n
m) or combn(x
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