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REAL_RAT_INV_CONV : term -> thm

SYNOPSIS
Conversion to invert a rational constant of type :real.

DESCRIPTION
The call REAL_RAT_INV_CONV `inv c`, where c is a rational constant of type :real, returns the theorem |- inv c = d where d is the canonical rational constant that is equal to c's multiplicative inverse (reciprocal). The constant c may be an integer constant (&n or -- &n), a ratio (&p / &q or -- &p / &q), or a decimal (#DDD.DDDD or #DDD.DDDDeNN). The returned value d is always put in the form &p / &q or -- &p / &q with q > 1 and p and q sharing no common factor, or simply &p or -- &p when that is impossible.

FAILURE CONDITIONS
Fails if applied to a term that is not the multiplicative inverse function applied to one of the permitted forms of rational constant of type :real, or if the constant is zero.

EXAMPLE
  # REAL_RAT_INV_CONV `inv(-- &5 / &9)`;;
  val it : thm = |- inv (-- &5 / &9) = -- &9 / &5

SEE ALSO
REAL_RAT_ABS_CONV, REAL_RAT_ADD_CONV, REAL_RAT_DIV_CONV, REAL_RAT_EQ_CONV, REAL_RAT_GE_CONV, REAL_RAT_GT_CONV, REAL_RAT_LE_CONV, REAL_RAT_LT_CONV, REAL_RAT_MAX_CONV, REAL_RAT_MIN_CONV, REAL_RAT_MUL_CONV, REAL_RAT_NEG_CONV, REAL_RAT_POW_CONV, REAL_RAT_REDUCE_CONV, REAL_RAT_RED_CONV, REAL_RAT_SGN_CONV, REAL_RAT_SUB_CONV.