What are the three main settings in “A Rage in Harlem” that you can analyze?

Setting is defined as the total summary of all relevant locations and times in which a story takes place.
In Chester Himes's A Rage in Harlem, the primary setting, of course, is the titular borough of New York City in which most of the action takes place. One might consider the descriptions the narrator provides that evoke an emotion rather than mere physical landmarks:

a city of black people who are convulsed in a desperate living, like the voracious churning of millions of hungry cannibal fish. Blind mouths eating their own guts. Stick in a hand and draw back a nub.

Another setting you might consider worthy of analysis is the 1950's era in which the novel was published. Written as a sort of crime noir, the novel’s time period is relevant to understanding the political dynamics among the various characters and their motivations.
Finally, you might consider a more specific place, such as the police station where Gravedigger and Coffin Ed work. Although these two characters play a relatively minor role in the novel’s primary action, the formal, “proper” setting of the police station serves as a major contrast to the seedy, mysterious places that dominate the backdrop of the novel’s action.