matplotlib / matplotlib/mplfinance

Wrong location of Y-tick-labels.

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Python
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Description

Dear Mr. Goldfarb, once again I ask for your assistance in solving a problem. I'm still working on an all in one solution, but this time it is build around mplfinance and pandas_ta. As you can see in the screen dump, this plot is based on the default style of mplfinance. But I can change it on the fly by the button 'settings'. With settings you can choose out all the mplfinance types and styles. It is too hard to discus at once all the options i wrote so far. But it is interactive and based on tkinter and TkAgg or Agg backend.

The problem:
Adding a secondary Yaxis on the first plot of mplfinance 'the date-price plot'. The secondary Y-axis contain the fibonacci levels and the values feeded by a dict. As you can see the lines will be plot correct, no problem. The major failure is that the Y-tick-labels don't follow the Y- ticks. The tick-labels always will be plotted on de opposite site of the Y-ticks. Whatever I try. The 'twinx' is not a solution because it block the cursor acces to the first plot axes[0] the 'date-price plot', for a dark reason. I don't offer the cursor for it, because it works fast and fine. It plot the date and price value left on the bottom toolbar. The minor problem after adding the fibonacci levels, the grid of the price ticks will be lost. Below you will find the function how I plot the fibonacci lines and config of the secondary Y-axis. I will hope You will and can help me ? Many thanks in advance.

```python
def set_fibs():
global fib, axes
bolds = ['0.0', '100.0', '200.0', '300.0', '400.0', '500.0', '600.0', '700.0', '800.0', '900.0']
yliFor = []
yliLoc = []
limit = axes[0].get_ylim()
y2 = axes[0].secondary_yaxis('left')
y2.set_ylim(limit[0], limit[1])
for k, v in fib.items():
if v <= limit[1] and v >= limit[0]:
tmp = k + ': ' + "{:.3f}".format(v)
yliFor.append(tmp)
yliLoc.append(v)
if any(sb in k for sb in bolds):
axes[0].axhline(v, linestyle='solid', color='brown', lw=0.9, label=k)
else:
if 'Fs' in k:
axes[0].axhline(v, linestyle='dashed', color='orange', lw=0.5, label=k)
else:
axes[0].axhline(v, linestyle='dashed', color='brown', lw=0.5, label=k)
y2.axes.set_yticks(yliLoc)
y2.axes.yaxis.set_ticklabels(yliFor, fontsize=8, color='brown')
for it in y2.get_yticklabels():
txt = it.get_text()
if 'Fs' in txt:
it.set_color('orange')
y2.set_ylabel('Fibonacci', color='brown')
return
```

![screendump](https://user-images.githubusercontent.com/25880296/214066090-505e77f4-039a-40ad-a2cd-5cb23472f878.jpg)

[data.zip](https://github.com/matplotlib/mplfinance/files/10480799/data.zip)

Contributor guide

Open the contributing guide

Research direction

Start by reproducing the reported behavior from the `set_fibs()` function in the issue, especially `axes[0].secondary_yaxis('left')` and the tick-label configuration, using the linked screenshot and data.zip. Done would mean determining whether the secondary Y-axis labels can align with their ticks without losing the primary price grid; no repository file or test is named.

Written by the indexing model from the issue text.

Assessment

Tech stack
matplotlib, python
Domain
data-visualization
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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