How to color cells efficiently?

I’m working with:

LibreOffice     4.2.3.3
MacOS X         10.8.5

I have to manage a few tables so as to fill their cells to express a level (temperature for example).
Here is an example of the background-color scheme I would like to achieve:
LibreOffice table with colors

The function to implement is:

if (cell-content == 1) then color-background = green
if (cell-content == 2) then color-background = yellow
[...]

I already have a pretty good idea of a bad method:

  1. select cell
  2. select menu > Table > Table Properties...
  3. select Background, choose Background color, click OK
  4. goto 1 until deadline

What are the efficient ways to achieve this color filling efficiently
and so as to be able to change the overall color scheme?

Is there a right method with “conditional paragraph styles” (p. 216 of Writer Guide 4.0)?

Is there a right method with “formulas” ( p. 282 of Writer Guide 4.0)?

Is it possible to get a function like a “cell-style” so as to apply it manually to a given set of cells?

Hallo

Select the Range in Question and goto →Format→Conditional Formatting →Colorbar

Edit forget this answer I realized too late that you’re refers to writer-tables

Under the Format menu I haven’t any Conditional Formatting entry.
I don’t get it even when I select a cell of my table.
Is this a dynamical menu I could get only under certain conditions?

You are welcome to laugh: I did the same sort of error. I searched on Google: “LibraOffice Applying Conditional Formatting” and read many pages scratching my head. “Where are all these fantastic functions? Is my version that old? Are my eyes that tired?”

I don’t think there is or will be such a feature in Writer. Insert a Calc OLE object better.

(Editing with regard to the comments)

The formulas are there, but all the formatting styles are lost. …

Working with formulae in a Writer table is complicated, time-consuming, and error-prone as I would judge. Getting rid of it might pay for a few complications on the other hand.

I am a bit curios now and would like to see a realistic example of your style-of-using-styles.

I thought to this way. But this will lead me to another problem of the same size:
“how will I set the paragraph formatting efficiently of many cells” ?
I would like to manage within a technical document tables with text correctly formatted and cells correctly formatted. These tables contains about half an hundred cells.

To make a try, I just copied one of my table in writer and pasted it within calc.
The formulas are there, but all the formatting styles are lost.

For only few different Values try:
→edit→find&replace→search for 1 →→findall and choose the Backcolor you want

repeat previous with the other numbers.