Automation and Make

Solutions

Lesson 02-makefiles

Write two new rules

Write a new rule for last.dat, created from books/last.txt.

Update the dats rule with this target.

Write a new rule for analysis.tar.gz, which creates an archive of the data files. The rule needs to:

Depend upon each of the three .dat files.
Invoke the action tar -czf analysis.tar.gz isles.dat abyss.dat last.dat

Update clean to remove analysis.tar.gz.

# Count words.
.PHONY : dats
dats : isles.dat abyss.dat last.dat

isles.dat : books/isles.txt
        python wordcount.py books/isles.txt isles.dat

abyss.dat : books/abyss.txt
        python wordcount.py books/abyss.txt abyss.dat

last.dat: books/last.txt
        python wordcount.py books/last.txt last.dat

analysis.tar.gz: isles.dat abyss.dat last.dat
        tar -czf analysis.tar.gz isles.dat abyss.dat last.dat

.PHONY : clean
clean :
        rm -f *.dat
        rm -f analysis.tar.gz

Lesson 03-variables

Update dependencies

What will happen if you now execute:

$ touch *.dat
$ make analysis.tar.gz

nothing
all files recreated
only .dat files recreated
only analysis.tar.gz recreated

4.) only analysis.tar.gz recreated.

You can check that *.dat is being expanded in the target of the rule for analysis.tar.gz by echoing the value of the automatic variable $^ (all dependencies of the current rule).

analysis.tar.gz: *.dat
    @echo $^
    tar -czf $@ $^

The rules for *.dat are not executed because their corresponding .txt files haven’t been modified.

If you run:

    $ touch *.dat
    $ touch books/*.txt
    $ make analysis.tar.gz

You will find that the .dat files as well as analysis.tar.gz are recreated.

Rewrite `.dat` rules to use automatic variables

Rewrite each .dat rule to use the automatic variables $@ (‘the target of the current rule’) and $< (‘the first dependency of the current rule’).

# Count words.
.PHONY : dats
dats : isles.dat abyss.dat last.dat

isles.dat : books/isles.txt
        python wordcount.py $< $@

abyss.dat : books/abyss.txt
        python wordcount.py $< $@

last.dat: books/last.txt
        python wordcount.py $< $@

analysis.tar.gz: *.dat
        tar -czf $@ $^

.PHONY : clean
clean :
        rm -f *.dat
        rm -f analysis.tar.gz

Lesson 06-variables

Use variables

Update Makefile so that the %.dat and analysis.tar.gz rules reference the variables COUNT_SRC and COUNT_EXE.

# Count words.
COUNT_SRC=wordcount.py
COUNT_EXE=python $(COUNT_SRC)

.PHONY : dats
dats : isles.dat abyss.dat last.dat

%.dat : books/%.txt COUNT_SRC
    $(COUNT_EXE) $< $*.dat

# Generate archive file.
analysis.tar.gz : *.dat COUNT_SRC
    tar -czf $@ $^

.PHONY : clean
clean :
        rm -f *.dat
        rm -f analysis.tar.gz

Lesson 08-variables

Extend the Makefile to create JPEGs

Add new rules, update existing rules, and add new macros to:

Create .jpg files from .dat files using plotcount.py.
Add the script and .jpg files to the archive.
Remove all auto-generated files (.dat, .jpg, analysis.tar.gz).

 # config.mk
 # Count words script.
COUNT_SRC=wordcount.py
COUNT_EXE=python $(COUNT_SRC)

# Plot word counts script.
PLOT_SRC=plotcount.py
PLOT_EXE=python $(PLOT_SRC)

# Makefile
include config.mk

TXT_FILES=$(wildcard books/*.txt)
DAT_FILES=$(patsubst books/%.txt, %.dat, $(TXT_FILES))
JPG_FILES=$(patsubst books/%.txt, %.jpg, $(TXT_FILES))

# Count words.
%.dat : books/%.txt $(COUNT_SRC)
    $(COUNT_EXE) $< $*.dat

# Plot word counts.
%.jpg : %.dat $(PLOT_SRC)
    $(PLOT_EXE) $*.dat $*.jpg

.PHONY : clean
clean :
    rm -f $(DAT_FILES)
    rm -f $(JPG_FILES)
    rm -f analysis.tar.gz

.PHONY : dats
dats : $(DAT_FILES)

.PHONY : jpgs
jpgs : $(JPG_FILES)

analysis.tar.gz : $(DAT_FILES) $(JPG_FILES) $(COUNT_SRC) $(PLOT_SRC)
    tar -czf $@ $^

.PHONY : variables
variables:
    @echo TXT_FILES: $(TXT_FILES)
    @echo DAT_FILES: $(DAT_FILES)
    @echo JPG_FILES: $(JPG_FILES)