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In grade school, numbers that use a positional notation along with a decimal point (to delimit integer and fractional parts of a number are called "decimals". This "point" notation is easily generalized to any base, e.g., in base 2, we can write the number 101.11, and the point is then called a binary point. But what is the number itself called—a "binary"? (doesn't sound right, somehow, but it is analogous to the base 10 term "decimal"). Surely we can't continue to call it a "decimal" given that the base isn't 10; that definitely doesn't seem right.

Is there a base-independent term for a positional number containing a radix point?

Thank you

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    I don't call numbers written in decimal form "decimals" either, I call them numbers written in decimal form, or decimal expansions. I would call a number expressed in base $p$ a number expressed in base $p$, or the base $p$ expansion of the number. In some cases there are special names, like binary expansions for $p=2$, ternary expansions for $p=3$, octal and hexadecimal (8 & 16), and I don't know what else. Another concern is the terminology analogous to "digit". For binary there are "bits", but I don't know about other bases, even $p=3$; I've jokingly called them "trigits" in that case.2011-12-21
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    Yes but "a number expressed in base _p_" doesn't have to contain a radix point (it could be an integer), so I don't see how that terminology distinguishes numbers that contain a radix point from numbers that don't.2011-12-21
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    Jack: Doesn't "noninteger" suffice in that case, or "fraction" if you prefer? I.e., a base $p$ expansion of a noninteger is precisely the type of thing that requires a radix point to be expressed in base $p$.2011-12-21
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    @Jonas: Well, I guess what I'm really looking for is a terminology that distinguishes fractional numbers notated using the vinculum ("fraction bar") vs. the radix point.2011-12-21
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    @MichaelHardy: Is that supposed to be funny? If you find my question flawed in some way, explaining why you think so would be much more useful to me than sarcasm.2011-12-22
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    @Jack : There was not a trace of sarcasm in my comment.2011-12-22
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    "Is there a base-independent term for a positional number containing a radix point?" -- Yes, it's called a *numeral in radix point notation*. ("Numeral" is the proper term for what you're calling a "number".)2011-12-22
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    @MichaelHardy: Well in that case my apologies, and I appreciate your response, but it's just too cryptic for me to understand. If you would be willing to elaborate on your answer I'd appreciate it. Thanks.2011-12-22
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    @r.e.s.: Yes, I like that distinction, thanks. So the _numeral_ "$\frac{1}{10}$", in "fraction-bar" notation (or perhaps "common fraction or vulgar fraction notation), represents the decimal fraction that we call "one-tenth" (assuming base ten), and the _numeral_ "0.1" represents the exact same number in "decimal point" notation (which generalizes as "radix point" notation.)2011-12-22

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