Consistent usage of whitespaces across gallery and tutorial examples

[yvonnefroehlich]

Description of proposed changes

Fixes#2013

---

Overview of affected examples

• Cross-check in the end regarding completeness

Tutorials

• Frames, ticks, titles, and labels (including explanation in section Title)
• Plotting data points

Gallery

• Line fronts
• Line styles
• Roads
• Vector heads and tails
• Color points by categories
• Points with varying transparency
• Calculating grid gradient and radiance
• Clipping grid values
• 3D Scatter plots
• Blockmean
• Histogram
• Colorbar

---

Reminders

• Run make format and make check to make sure the code follows the style guide.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If wrapping a new module, open a 'Wrap new GMT module' issue and submit reasonably-sized PRs.
• If adding new functionality, add an example to docstrings or tutorials.

Slash Commands

You can write slash commands (/command) in the first line of a comment to perform
specific operations. Supported slash commands are:

• /format: automatically format and lint the code
• /test-gmt-dev: run full tests on the latest GMT development version

[yvonnefroehlich]

In the section Title of the Tutorial 'Frames, ticks, titles, and labels':

################################################################################ Title# -----## The figure title can be set by passing **+t**\ *title* to the ``frame``# parameter of :meth:`pygmt.Figure.basemap`. Passing multiple arguments to# ``frame`` can be done by using a list, as show in the example below.fig=pygmt.Figure()
# region="IS" specifies Iceland using the ISO country codefig.coast(shorelines="1/0.5p", region="IS", projection="M25c")
fig.basemap(frame=["a", "+tIceland"])
fig.show()
################################################################################ To use a title with multiple words, the title must be placed inside another# set of quotation marks. To prevent the quotation marks from appearing in the# figure title, the ``frame`` parameter can be passed in single quotation marks# and the title can be passed in double quotation marks.fig=pygmt.Figure()
# region="TT" specifies Trinidad and Tobagofig.coast(shorelines="1/0.5p", region="TT", projection="M25c")
fig.basemap(frame=["a", '+t"Trinidad and Tobago"'])
fig.show()

• I would remove the part, which explains the double-quotation-mark trick.
• I would choose (and adjust) the code for the 'Trinidad and Tobago' map as an example for adding a title, and removed the code for the 'Island' map.

@seisman: Is this fine, or do you prefer to go with the 'Island' map as an example?

[seisman]

• I would remove the part, which explains the double-quotation-mark trick.
• I would choose (and adjust) the code for the 'Trinidad and Tobago' map as an example for adding a title, and removed the code for the 'Island' map.

Both sound good to me!

[seisman]

This PR looks good. Are there any more changes you want to make in this PR?

[seisman]

I think we also need to update a few tests.

tests/test_basemap.py: frame=['x1p+l"Crustal age"', "y500+lDepth"],
tests/test_config.py: region=[0, 10, 0, 10], projection="X5c/5c", frame=["af", '+t"Blue Annotation"']
tests/test_config.py: frame=['xaf+l"red label"', "yaf", '+t"red annotation"'],
tests/test_config.py: frame=["af", '+t"Blue Annotation"'],

These tests can be updated in this PR or in a separate PR.

[yvonnefroehlich]

This PR looks good. Are there any more changes you want to make in this PR?

Regarding the gallery and tutorials, I think I have found and changed all affected examples.

I think we also need to update a few tests.

Good point! Yes.

These tests can be updated in this PR or in a separate PR.

There is no real preference from my side on this. I can also open a new PR for updating the tests.

[seisman]

Good to merge.

[weiji14]

I think we also need to update a few tests.

tests/test_basemap.py: frame=['x1p+l"Crustal age"', "y500+lDepth"],
tests/test_config.py: region=[0, 10, 0, 10], projection="X5c/5c", frame=["af", '+t"Blue Annotation"']
tests/test_config.py: frame=['xaf+l"red label"', "yaf", '+t"red annotation"'],
tests/test_config.py: frame=["af", '+t"Blue Annotation"'],

These tests can be updated in this PR or in a separate PR.

Perhaps we should keep a few unit tests around that use the nested quotes, as a regression test to ensure backwards compatibility is preserved?

[seisman]

I think we also need to update a few tests.

tests/test_basemap.py: frame=['x1p+l"Crustal age"', "y500+lDepth"],
tests/test_config.py: region=[0, 10, 0, 10], projection="X5c/5c", frame=["af", '+t"Blue Annotation"']
tests/test_config.py: frame=['xaf+l"red label"', "yaf", '+t"red annotation"'],
tests/test_config.py: frame=["af", '+t"Blue Annotation"'],

These tests can be updated in this PR or in a separate PR.

Perhaps we should keep a few unit tests around that use the nested quotes, as a regression test to ensure backwards compatibility is preserved?

We already have the following test in docstrings. Do you think it's enough?

pygmt/pygmt/helpers/utils.py

Lines 189 to 198 in 4902687

	>>> print(
	... build_arg_string(
	... dict(
	... B=["af", "WSne+tBlank Space"],
	... F='+t"Empty Spaces"',
	... l="'Void Space'",
	... ),
	... )
	... )
	-BWSne+tBlank\040Space -Baf -F+t"Empty\040\040Spaces" -l'Void\040Space'

[weiji14]

I think we also need to update a few tests.

tests/test_basemap.py: frame=['x1p+l"Crustal age"', "y500+lDepth"],
tests/test_config.py: region=[0, 10, 0, 10], projection="X5c/5c", frame=["af", '+t"Blue Annotation"']
tests/test_config.py: frame=['xaf+l"red label"', "yaf", '+t"red annotation"'],
tests/test_config.py: frame=["af", '+t"Blue Annotation"'],

These tests can be updated in this PR or in a separate PR.

Perhaps we should keep a few unit tests around that use the nested quotes, as a regression test to ensure backwards compatibility is preserved?

We already have the following test in docstrings. Do you think it's enough?

pygmt/pygmt/helpers/utils.py

Lines 189 to 198 in 4902687

	>>> print(
	... build_arg_string(
	... dict(
	... B=["af", "WSne+tBlank Space"],
	... F='+t"Empty Spaces"',
	... l="'Void Space'",
	... ),
	... )
	... )
	-BWSne+tBlank\040Space -Baf -F+t"Empty\040\040Spaces" -l'Void\040Space'

Oh yes true. That one should be enough.