Abstract: A first encoding unit encodes, within the compression target data, each part with a sequence of the same value into the number of consecutive runs of the value. A decomposing unit decomposes the number of consecutive runs of the same value into an addition of integers belonging to a predetermined integer group. A calculating unit calculates the probability of occurrence of each integer obtained by the decomposition. A second encoding unit encodes each integer by assigning shorter codes to integers with higher probabilities of occurrence.

Abstract: A computer receives a retrieval request with a retrieval character string, adds control information to a region corresponding to code information included in a management region used for extending encoded data when an extension result of the code information matches a first character of the retrieval character string when the encoded data to be retrieved is sequentially extended in response to the retrieval request, and performs collation processing between the retrieval character string and character string information corresponding to data of the extension result of the code information when the control information is added to a partial region corresponding to code information to be extended in the extension.

Abstract: An extracting method includes storing to a storage device: files that include character units; first index information indicating which file includes at least one character unit in a character unit group having a usage frequency less than a predetermined frequency and among character units having common information in a predetermined portion, the usage frequency indicating the extent of files having a given character unit; second index information indicating which file includes a first character unit having a usage frequency at least equal to the predetermined frequency and among the character units having common information in a predetermined portion; and referring to the first and second index information to extract a file having character units in the first and second index information, when a request is received for extraction of a file having the first character unit and a second character unit that is included in the character unit group.

Abstract: A generation apparatus includes a processor configured to generate existence information indicating that character information including a plurality of continuing characters is included in the file, and in a case that first adscript designation and second adscript designation following to the first adscript designation are included in the file, the first adscript designation designating that first character information is written down with second character information, the second adscript designation designating that third character information is written down with fourth character information, generate another existence information indicating that another character information, which includes an end part of the first character information and a head part of the fourth character information following the end part, is included in the file.

Abstract: A retrieving apparatus includes a processor that specifies in each tier of synonym dictionary data, classification codes of a search word in a search character string and those of a comparison word in character strings for comparison; extracts from among the specified classification codes, classification codes in a specific tier; judges for each character string for comparison, whether the extracted classification code of the search word and that of the comparison word match; counts for the specific tier, matching classification codes; determines based on the count, whether a character string is to be excluded whose classification code of the comparison word for the specific tier does not match that of the search word; calculates based on the specified classification code of the search word and that of the comparison word in the character string not to be excluded, similarity between the two character strings; and outputs a calculation result.

Abstract: A searching apparatus includes a processor configured to receive searching character information, in a case that document data includes a designation that first character information and second character information are provided in adscript description, to copy state information indicating a state of a collating process of the searching character information on third character information in front of the designation in the document data, to update the state information based on a result of collating the first character information with the searching character information, and to update the copied state information based on a result of collating the second character information with the searching character information.

Abstract: An extracting method includes storing to a storage device: files that include character units; first index information indicating which file includes at least one character unit in a character unit group having a usage frequency less than a predetermined frequency and among character units having common information in a predetermined portion, the usage frequency indicating the extent of files having a given character unit; second index information indicating which file includes a first character unit having a usage frequency at least equal to the predetermined frequency and among the character units having common information in a predetermined portion; and referring to the first and second index information to extract a file having character units in the first and second index information, when a request is received for extraction of a file having the first character unit and a second character unit that is included in the character unit group.