Error message popped up

ssumd · September 14, 2018, 8:18pm

Hi,
I am having problem with ggplot2. When I type

ggplot(Data,
       aes(x = Season, y = Aeromonas)) +
  geom_boxplot(fill='lightblue', color='blue') +
  geom_point(color='darkblue')

a perfect graph showed up.

But when I type

ggplot(Data,
       aes(x = Water type, y = Aeromonas)) +
  geom_boxplot(fill='lightblue', color='blue') +
  geom_point(color='darkblue')

This error message popped up

Error: Cannot add ggproto objects together. Did you forget to add this object to a ggplot object?

Please help me. What's the problem?

dlsweet · September 14, 2018, 8:25pm

I'm not sure what that error message means without being able to recreate it through a reprex but if you copied that code exactly, you need `` around Water Type, so it should be:

ggplot(Data,
aes(x = `Water type`, y = Aeromonas)) +
geom_boxplot(fill='lightblue', color='blue') +
geom_point(color='darkblue')

If that doesn't work, look here to make a reprex:

FAQ: What's a reproducible example (`reprex`) and how do I create one? meta

Why reprex? Getting unstuck is hard. Your first step here is usually to create a reprex, or reproducible example. The goal of a reprex is to package your code, and information about your problem so that others can run it and feel your pain. Then, hopefully, folks can more easily provide a solution. What's in a Reproducible Example? Parts of a reproducible example: background information - Describe what you are trying to do. What have you already done? complete set up - include any library() calls and data to reproduce your issue. data for a reprex: Here's a discussion on setting up data for a reprex make it run - include the minimal code required to reproduce your error on the data…

ssumd · September 14, 2018, 8:41pm

Thanks dlsweet. I tried with your code. Now instead of dividing my water type into 4 different groups, it makes one single group. Like this,

dlsweet · September 14, 2018, 8:50pm

Can you create a reprex?

aosmith · September 14, 2018, 10:25pm

Are you sure you used back ticks and not single quotes around Water type? Back ticks are on the same key as the tilde on my keyboard.

ssumd · September 18, 2018, 10:23pm

No. I don't know how to create a reprex.

ssumd · September 18, 2018, 10:24pm

Yes. I just copied and pasted the code and ran. Nothing worked.

kmprioli · September 18, 2018, 11:14pm

Hi there Sultana! Creating a reprex (short for reproducible example) is very easy!

First, install the reprex package: install.packages("reprex") and load its library: library(reprex)

Then, follow the instructions here to create the reprex. The link I provided includes a discussion of how to add your data to the reprex, which will probably be key to helping you get the right eyes on this.

A reprex will ensure we're all looking at the same data and code, which helps us to help you!

One more thought: you mentioned wanting to see four different groups in your boxplot. It sounds like you may be interested in either faceting or grouping by season. If that's the case, you may want to consider (for example) using facet_wrap() with your Season variable.

I hope this helps!

ssumd · September 19, 2018, 12:26am

Hi Katherine,

Thanks for this help. It helped.